* [RFC/PATCH 2/5] HDQ/1-wire support for OMAP2430/3430
@ 2007-12-10 10:17 Madhusudhan Chikkature Rajashekar
2007-12-11 11:20 ` Trilok Soni
0 siblings, 1 reply; 3+ messages in thread
From: Madhusudhan Chikkature Rajashekar @ 2007-12-10 10:17 UTC (permalink / raw)
To: 'Evgeniy Polyakov', linux-omap-open-source; +Cc: linux-omap
This patch adds OMAP2430/3430 HDQ/1-Wire driver support.
Signed-off-by: Madhusudhan Chikkature<madhu.cr@ti.com>
---
drivers/w1/masters/Kconfig | 8
drivers/w1/masters/Makefile | 1
drivers/w1/masters/omap_hdq.c | 653 ++++++++++++++++++++++++++++++++++++++++
include/asm-arm/arch-omap/hdq.h | 23 +
4 files changed, 685 insertions(+)
Index: linux-omap-hdq-new/drivers/w1/masters/omap_hdq.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-omap-hdq-new/drivers/w1/masters/omap_hdq.c 2007-12-06 17:14:30.189291891 +0530
@@ -0,0 +1,653 @@
+/*
+ * drivers/w1/masters/omap_hdq.c
+ *
+ * Copyright (C) 2007 Texas Instruments, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <asm/irq.h>
+#include <asm/hardware.h>
+#include <asm/arch/hdq.h>
+
+#include "../w1.h"
+#include "../w1_int.h"
+
+#define MOD_NAME "OMAP_HDQ:"
+
+#define OMAP_HDQ_REVISION 0x00
+#define OMAP_HDQ_TX_DATA 0x04
+#define OMAP_HDQ_RX_DATA 0x08
+#define OMAP_HDQ_CTRL_STATUS 0x0c
+#define OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK (1<<6)
+#define OMAP_HDQ_CTRL_STATUS_CLOCKENABLE (1<<5)
+#define OMAP_HDQ_CTRL_STATUS_GO (1<<4)
+#define OMAP_HDQ_CTRL_STATUS_INITIALIZATION (1<<2)
+#define OMAP_HDQ_CTRL_STATUS_DIR (1<<1)
+#define OMAP_HDQ_CTRL_STATUS_MODE (1<<0)
+#define OMAP_HDQ_INT_STATUS 0x10
+#define OMAP_HDQ_INT_STATUS_TXCOMPLETE (1<<2)
+#define OMAP_HDQ_INT_STATUS_RXCOMPLETE (1<<1)
+#define OMAP_HDQ_INT_STATUS_TIMEOUT (1<<0)
+#define OMAP_HDQ_SYSCONFIG 0x14
+#define OMAP_HDQ_SYSCONFIG_SOFTRESET (1<<1)
+#define OMAP_HDQ_SYSCONFIG_AUTOIDLE (1<<0)
+#define OMAP_HDQ_SYSSTATUS 0x18
+#define OMAP_HDQ_SYSSTATUS_RESETDONE (1<<0)
+
+#define OMAP_HDQ_FLAG_CLEAR 0
+#define OMAP_HDQ_FLAG_SET 1
+#define OMAP_HDQ_TIMEOUT (HZ/5)
+
+#define OMAP_HDQ_MAX_USER 4
+
+DECLARE_WAIT_QUEUE_HEAD(hdq_wait_queue);
+int W1_ID;
+
+struct hdq_data {
+ resource_size_t hdq_base;
+ struct semaphore hdq_semlock;
+ int hdq_usecount;
+ struct clk *hdq_ick;
+ struct clk *hdq_fck;
+ u8 hdq_irqstatus;
+ spinlock_t hdq_spinlock;
+};
+
+static struct hdq_data *hdq_data;
+
+static int __init omap_hdq_probe(struct platform_device *pdev);
+static int omap_hdq_remove(struct platform_device *pdev);
+
+static struct platform_driver omap_hdq_driver = {
+ .probe = omap_hdq_probe,
+ .remove = omap_hdq_remove,
+ .suspend = NULL,
+ .resume = NULL,
+ .driver = {
+ .name = "omap_hdq",
+ },
+};
+
+static u8 omap_w1_read_byte(void *data);
+static void omap_w1_write_byte(void *data, u8 byte);
+static u8 omap_w1_reset_bus(void *data);
+static void omap_w1_search_bus(void *data, u8 search_type,
+ w1_slave_found_callback slave_found);
+
+static struct w1_bus_master omap_w1_master = {
+ .read_byte = omap_w1_read_byte,
+ .write_byte = omap_w1_write_byte,
+ .reset_bus = omap_w1_reset_bus,
+ .search = omap_w1_search_bus,
+};
+
+/*
+ * HDQ register I/O routines
+ */
+static inline u8
+hdq_reg_in(u32 offset)
+{
+ return omap_readb(hdq_data->hdq_base + offset);
+}
+
+static inline u8
+hdq_reg_out(u32 offset, u8 val)
+{
+ omap_writeb(val, hdq_data->hdq_base + offset);
+ return val;
+}
+
+static inline u8
+hdq_reg_merge(u32 offset, u8 val, u8 mask)
+{
+ u8 new_val = (omap_readb(hdq_data->hdq_base + offset) & ~mask)
+ | (val & mask);
+ omap_writeb(new_val, hdq_data->hdq_base + offset);
+ return new_val;
+}
+
+/*
+ * Wait for one or more bits in flag change.
+ * HDQ_FLAG_SET: wait until any bit in the flag is set.
+ * HDQ_FLAG_CLEAR: wait until all bits in the flag are cleared.
+ * return 0 on success and -ETIMEOUT in the case of timeout.
+ */
+static int
+hdq_wait_for_flag(u32 offset, u8 flag, u8 flag_set, u8 *status)
+{
+ int ret = 0;
+ unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
+
+ if (flag_set == OMAP_HDQ_FLAG_CLEAR) {
+ /* wait for the flag clear */
+ while (((*status = hdq_reg_in(offset)) & flag)
+ && time_before(jiffies, timeout)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+ if (unlikely(*status & flag))
+ ret = -ETIMEDOUT;
+ } else if (flag_set == OMAP_HDQ_FLAG_SET) {
+ /* wait for the flag set */
+ while (!((*status = hdq_reg_in(offset)) & flag)
+ && time_before(jiffies, timeout)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+ if (unlikely(!(*status & flag)))
+ ret = -ETIMEDOUT;
+ } else
+ return -EINVAL;
+
+ return ret;
+}
+
+/*
+ * write out a byte and fill *status with HDQ_INT_STATUS
+ */
+static int
+hdq_write_byte(u8 val, u8 *status)
+{
+ int ret;
+ u8 tmp_status;
+ unsigned long irqflags;
+
+ *status = 0;
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ /* clear interrupt flags via a dummy read */
+ hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ /* ISR loads it with new INT_STATUS */
+ hdq_data->hdq_irqstatus = 0;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+
+ hdq_reg_out(OMAP_HDQ_TX_DATA, val);
+
+ /* set the GO bit */
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
+ /* wait for the TXCOMPLETE bit */
+ ret = wait_event_interruptible_timeout(hdq_wait_queue,
+ hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
+ if (unlikely(ret < 0)) {
+ pr_debug("wait interrupted");
+ return -EINTR;
+ }
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ *status = hdq_data->hdq_irqstatus;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ /* check irqstatus */
+ if (!(*status & OMAP_HDQ_INT_STATUS_TXCOMPLETE)) {
+ pr_debug("timeout waiting for TXCOMPLETE/RXCOMPLETE, %x",
+ *status);
+ return -ETIMEDOUT;
+ }
+
+ /* wait for the GO bit return to zero */
+ ret = hdq_wait_for_flag(OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_FLAG_CLEAR, &tmp_status);
+ if (ret) {
+ pr_debug("timeout waiting GO bit return to zero, %x",
+ tmp_status);
+ return ret;
+ }
+
+ return ret;
+}
+
+static irqreturn_t
+hdq_isr(int irq, void *arg)
+{
+ unsigned long irqflags;
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ hdq_data->hdq_irqstatus = hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ pr_debug("hdq_isr: %x", hdq_data->hdq_irqstatus);
+
+ if (hdq_data->hdq_irqstatus &
+ (OMAP_HDQ_INT_STATUS_TXCOMPLETE | OMAP_HDQ_INT_STATUS_RXCOMPLETE
+ | OMAP_HDQ_INT_STATUS_TIMEOUT)) {
+ /* wake up sleeping process */
+ wake_up_interruptible(&hdq_wait_queue);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static u8 omap_w1_reset_bus(void *data)
+{
+ return 0;
+}
+
+static void omap_w1_search_bus(void *data, u8 search_type,
+ w1_slave_found_callback slave_found)
+{
+ u64 module_id, rn_le, cs, id;
+
+ if (W1_ID)
+ module_id = W1_ID;
+ else
+ module_id = 0x1;
+
+ rn_le = cpu_to_le64(module_id);
+ /* HDQ might not obely truly the 1-wire spec.
+ * So calculate CRC based on module parameter.
+ */
+ cs = w1_calc_crc8((u8 *)&rn_le, 7);
+ id = (cs << 56) | module_id;
+
+ slave_found(data, id);
+}
+
+static int
+_omap_hdq_reset(void)
+{
+ int ret;
+ u8 tmp_status;
+
+ hdq_reg_out(OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_SOFTRESET);
+ /*
+ * Select HDQ mode & enable clocks.
+ * It is observed that INT flags can't be cleared via a read and GO/INIT
+ * won't return to zero if interrupt is disabled. So we always enable
+ * interrupt.
+ */
+ hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
+ OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
+
+ /* wait for reset to complete */
+ ret = hdq_wait_for_flag(OMAP_HDQ_SYSSTATUS,
+ OMAP_HDQ_SYSSTATUS_RESETDONE, OMAP_HDQ_FLAG_SET, &tmp_status);
+ if (ret)
+ pr_debug("timeout waiting HDQ reset, %x", tmp_status);
+ else {
+ hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
+ OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
+ hdq_reg_out(OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_AUTOIDLE);
+ }
+
+ return ret;
+}
+
+int
+omap_hdq_reset(void)
+{
+ int ret;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (!hdq_data->hdq_usecount) {
+ up(&hdq_data->hdq_semlock);
+ return -EINVAL;
+ }
+ ret = _omap_hdq_reset();
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+
+int
+omap_hdq_break()
+{
+ int ret;
+ u8 tmp_status;
+ unsigned long irqflags;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (!hdq_data->hdq_usecount) {
+ up(&hdq_data->hdq_semlock);
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ /* clear interrupt flags via a dummy read */
+ hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ /* ISR loads it with new INT_STATUS */
+ hdq_data->hdq_irqstatus = 0;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+
+ /* set the INIT and GO bit */
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_INITIALIZATION | OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
+ OMAP_HDQ_CTRL_STATUS_GO);
+
+ /* wait for the TIMEOUT bit */
+ ret = wait_event_interruptible_timeout(hdq_wait_queue,
+ hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
+ if (unlikely(ret < 0)) {
+ pr_debug("wait interrupted");
+ up(&hdq_data->hdq_semlock);
+ return -EINTR;
+ }
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ tmp_status = hdq_data->hdq_irqstatus;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ /* check irqstatus */
+ if (!(tmp_status & OMAP_HDQ_INT_STATUS_TIMEOUT)) {
+ pr_debug("timeout waiting for TIMEOUT, %x", tmp_status);
+ up(&hdq_data->hdq_semlock);
+ return -ETIMEDOUT;
+ }
+ /*
+ * wait for both INIT and GO bits rerurn to zero.
+ * zero wait time expected for interrupt mode.
+ */
+ ret = hdq_wait_for_flag(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
+ OMAP_HDQ_CTRL_STATUS_GO, OMAP_HDQ_FLAG_CLEAR,
+ &tmp_status);
+ if (ret)
+ pr_debug("timeout waiting INIT&GO bits return to zero, %x",
+ tmp_status);
+
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_hdq_break);
+
+int hdq_read_byte(u8 *val)
+{
+ int ret;
+ u8 status;
+ unsigned long irqflags;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (!hdq_data->hdq_usecount) {
+ up(&hdq_data->hdq_semlock);
+ return -EINVAL;
+ }
+
+ if (!(hdq_data->hdq_irqstatus & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
+ /*
+ * The RX comes immediately after TX. It
+ * triggers another interrupt before we
+ * sleep. So we have to wait for RXCOMPLETE bit.
+ */
+ {
+ unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
+ while (!(hdq_data->hdq_irqstatus
+ & OMAP_HDQ_INT_STATUS_RXCOMPLETE)
+ && time_before(jiffies, timeout)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+ }
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS, 0,
+ OMAP_HDQ_CTRL_STATUS_DIR);
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ status = hdq_data->hdq_irqstatus;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ /* check irqstatus */
+ if (!(status & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
+ pr_debug("timeout waiting for RXCOMPLETE, %x", status);
+ up(&hdq_data->hdq_semlock);
+ return -ETIMEDOUT;
+ }
+ }
+ /* the data is ready. Read it in! */
+ *val = hdq_reg_in(OMAP_HDQ_RX_DATA);
+ up(&hdq_data->hdq_semlock);
+
+ return 0;
+
+}
+
+int
+omap_hdq_get()
+{
+ int ret = 0;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (OMAP_HDQ_MAX_USER == hdq_data->hdq_usecount) {
+ pr_debug("attempt to exceed the max use count");
+ up(&hdq_data->hdq_semlock);
+ ret = -EINVAL;
+ } else {
+ hdq_data->hdq_usecount++;
+ try_module_get(THIS_MODULE);
+ if (1 == hdq_data->hdq_usecount) {
+ if (clk_enable(hdq_data->hdq_ick)) {
+ pr_debug("Can not enable ick\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ up(&hdq_data->hdq_semlock);
+ return -ENODEV;
+ }
+ if (clk_enable(hdq_data->hdq_fck)) {
+ pr_debug("Can not enable fck\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ up(&hdq_data->hdq_semlock);
+ return -ENODEV;
+ }
+
+ /* make sure HDQ is out of reset */
+ if (!(hdq_reg_in(OMAP_HDQ_SYSSTATUS) &
+ OMAP_HDQ_SYSSTATUS_RESETDONE)) {
+ ret = _omap_hdq_reset();
+ if (ret)
+ /* back up the count */
+ hdq_data->hdq_usecount--;
+ } else {
+ /* select HDQ mode & enable clocks */
+ hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
+ OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
+ hdq_reg_out(OMAP_HDQ_SYSCONFIG,
+ OMAP_HDQ_SYSCONFIG_AUTOIDLE);
+ hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ }
+ }
+ }
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_hdq_get);
+
+int
+omap_hdq_put()
+{
+ int ret = 0;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (0 == hdq_data->hdq_usecount) {
+ pr_debug("attempt to decrement use count when it is zero");
+ ret = -EINVAL;
+ } else {
+ hdq_data->hdq_usecount--;
+ module_put(THIS_MODULE);
+ if (0 == hdq_data->hdq_usecount) {
+ clk_disable(hdq_data->hdq_ick);
+ clk_disable(hdq_data->hdq_fck);
+ }
+ }
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_hdq_put);
+
+static u8 omap_w1_read_byte(void *data)
+{
+ u8 val;
+ int ret;
+
+ ret = hdq_read_byte(&val);
+ if (ret)
+ return -1;
+ return val;
+}
+
+static void omap_w1_write_byte(void *data, u8 byte)
+{
+ u8 status;
+
+ hdq_write_byte(byte, &status);
+ pr_debug("Ctrl status %x\n", status);
+ return;
+}
+
+static int __init omap_hdq_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ int ret, irq;
+ u8 rev;
+
+ if (!pdev)
+ return -ENODEV;
+
+ hdq_data = kmalloc(sizeof(*hdq_data), GFP_KERNEL);
+ if (!hdq_data)
+ return -ENODEV;
+
+ platform_set_drvdata(pdev, hdq_data);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENXIO;
+ }
+
+ hdq_data->hdq_base = res->start;
+
+ /* get interface & functional clock objects */
+ hdq_data->hdq_ick = clk_get(&pdev->dev, "hdq_ick");
+ hdq_data->hdq_fck = clk_get(&pdev->dev, "hdq_fck");
+
+ if (IS_ERR(hdq_data->hdq_ick) || IS_ERR(hdq_data->hdq_fck)) {
+ pr_debug("Can't get HDQ clock objects\n");
+ if (IS_ERR(hdq_data->hdq_ick)) {
+ ret = PTR_ERR(hdq_data->hdq_ick);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return ret;
+ }
+ if (IS_ERR(hdq_data->hdq_fck)) {
+ ret = PTR_ERR(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return ret;
+ }
+ }
+
+ hdq_data->hdq_usecount = 0;
+ sema_init(&hdq_data->hdq_semlock, 1);
+
+ if (clk_enable(hdq_data->hdq_ick)) {
+ pr_debug("Can not enable ick\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENODEV;
+ }
+
+ rev = hdq_reg_in(OMAP_HDQ_REVISION);
+ pr_info("OMAP HDQ Hardware Revision %c.%c. Driver in %s mode.\n",
+ (rev >> 4) + '0', (rev & 0x0f) + '0', "Interrupt");
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENXIO;
+ }
+
+ if (request_irq(irq, hdq_isr, IRQF_DISABLED, "OMAP HDQ",
+ &hdq_data->hdq_semlock)) {
+ pr_debug("request_irq failed\n");
+ clk_disable(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENODEV;
+ }
+ spin_lock_init(&hdq_data->hdq_spinlock);
+ /* don't clock the HDQ until it is needed */
+ clk_disable(hdq_data->hdq_ick);
+
+ ret = w1_add_master_device(&omap_w1_master);
+ if (ret) {
+ pr_debug("Failure in registering w1 master\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int omap_hdq_remove(struct platform_device *pdev)
+{
+ down_interruptible(&hdq_data->hdq_semlock);
+ if (0 != hdq_data->hdq_usecount) {
+ pr_debug("removed when use count is not zero\n");
+ return -EBUSY;
+ }
+ up(&hdq_data->hdq_semlock);
+
+ /* remove module dependency */
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ free_irq(INT_24XX_HDQ_IRQ, &hdq_data->hdq_semlock);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+
+ return 0;
+}
+
+static int __init
+omap_hdq_init(void)
+{
+ return platform_driver_register(&omap_hdq_driver);
+}
+
+static void __exit
+omap_hdq_exit(void)
+{
+ platform_driver_unregister(&omap_hdq_driver);
+}
+
+module_init(omap_hdq_init);
+module_exit(omap_hdq_exit);
+
+module_param(W1_ID, int, S_IRUSR);
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("HDQ driver Library");
+MODULE_LICENSE("GPL");
Index: linux-omap-hdq-new/drivers/w1/masters/Kconfig
===================================================================
--- linux-omap-hdq-new.orig/drivers/w1/masters/Kconfig 2007-11-27 20:04:44.000000000 +0530
+++ linux-omap-hdq-new/drivers/w1/masters/Kconfig 2007-12-04 17:58:44.000000000 +0530
@@ -42,5 +42,13 @@
in HP iPAQ devices like h5xxx, h2200, and ASIC3-based like
hx4700.
+config HDQ_MASTER_OMAP
+ tristate "OMAP HDQ driver"
+ depends on ARCH_OMAP2430 || ARCH_OMAP34XX
+ help
+ Say Y here if you want support for the 1-wire or HDQ Interface
+ on an OMAP processor.
+
+
endmenu
Index: linux-omap-hdq-new/drivers/w1/masters/Makefile
===================================================================
--- linux-omap-hdq-new.orig/drivers/w1/masters/Makefile 2007-11-27 20:04:44.000000000 +0530
+++ linux-omap-hdq-new/drivers/w1/masters/Makefile 2007-12-04 08:55:21.000000000 +0530
@@ -6,3 +6,4 @@
obj-$(CONFIG_W1_MASTER_DS2490) += ds2490.o
obj-$(CONFIG_W1_MASTER_DS2482) += ds2482.o
obj-$(CONFIG_W1_MASTER_DS1WM) += ds1wm.o
+obj-$(CONFIG_HDQ_MASTER_OMAP) += omap_hdq.o
Index: linux-omap-hdq-new/include/asm-arm/arch-omap/hdq.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-omap-hdq-new/include/asm-arm/arch-omap/hdq.h 2007-12-04 08:55:21.000000000 +0530
@@ -0,0 +1,23 @@
+/*
+ * include/asm-arm/arch-omap2/hdq.h
+ *
+ * Copyright (C) 2006-2007 Texas Instruments, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ */
+
+#ifndef __ASM_OMAP2_HDQ_H__
+#define __ASM_OMAP2_HDQ_H__
+
+/* Note the following API has to be called in a process context */
+
+int omap_hdq_get(void); /* request the HDQ block */
+int omap_hdq_put(void); /* release the HDQ block */
+
+int omap_hdq_reset(void); /* reset the HDQ block */
+int omap_hdq_break(void); /* reset the slave by sending it a break pulse */
+
+#endif
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [RFC/PATCH 2/5] HDQ/1-wire support for OMAP2430/3430
2007-12-10 10:17 [RFC/PATCH 2/5] HDQ/1-wire support for OMAP2430/3430 Madhusudhan Chikkature Rajashekar
@ 2007-12-11 11:20 ` Trilok Soni
0 siblings, 0 replies; 3+ messages in thread
From: Trilok Soni @ 2007-12-11 11:20 UTC (permalink / raw)
To: Madhusudhan Chikkature Rajashekar
Cc: Evgeniy Polyakov, linux-omap, linux-omap-open-source
Hi Madhu,
On Dec 10, 2007 3:47 PM, Madhusudhan Chikkature Rajashekar
<madhu.cr@ti.com> wrote:
> This patch adds OMAP2430/3430 HDQ/1-Wire driver support.
>
> Signed-off-by: Madhusudhan Chikkature<madhu.cr@ti.com>
>
> ---
> drivers/w1/masters/Kconfig | 8
> drivers/w1/masters/Makefile | 1
> drivers/w1/masters/omap_hdq.c | 653 ++++++++++++++++++++++++++++++++++++++++
> include/asm-arm/arch-omap/hdq.h | 23 +
> 4 files changed, 685 insertions(+)
>
> Index: linux-omap-hdq-new/drivers/w1/masters/omap_hdq.c
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux-omap-hdq-new/drivers/w1/masters/omap_hdq.c 2007-12-06 17:14:30.189291891 +0530
> @@ -0,0 +1,653 @@
> +/*
> + * drivers/w1/masters/omap_hdq.c
> + *
> + * Copyright (C) 2007 Texas Instruments, Inc.
> + *
> + * This file is licensed under the terms of the GNU General Public License
> + * version 2. This program is licensed "as is" without any warranty of any
> + * kind, whether express or implied.
> + *
> + */
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/interrupt.h>
> +#include <linux/err.h>
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <asm/irq.h>
> +#include <asm/hardware.h>
> +#include <asm/arch/hdq.h>
> +
> +#include "../w1.h"
> +#include "../w1_int.h"
> +
> +#define MOD_NAME "OMAP_HDQ:"
> +
> +#define OMAP_HDQ_REVISION 0x00
> +#define OMAP_HDQ_TX_DATA 0x04
> +#define OMAP_HDQ_RX_DATA 0x08
> +#define OMAP_HDQ_CTRL_STATUS 0x0c
> +#define OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK (1<<6)
> +#define OMAP_HDQ_CTRL_STATUS_CLOCKENABLE (1<<5)
> +#define OMAP_HDQ_CTRL_STATUS_GO (1<<4)
> +#define OMAP_HDQ_CTRL_STATUS_INITIALIZATION (1<<2)
> +#define OMAP_HDQ_CTRL_STATUS_DIR (1<<1)
> +#define OMAP_HDQ_CTRL_STATUS_MODE (1<<0)
> +#define OMAP_HDQ_INT_STATUS 0x10
> +#define OMAP_HDQ_INT_STATUS_TXCOMPLETE (1<<2)
> +#define OMAP_HDQ_INT_STATUS_RXCOMPLETE (1<<1)
> +#define OMAP_HDQ_INT_STATUS_TIMEOUT (1<<0)
> +#define OMAP_HDQ_SYSCONFIG 0x14
> +#define OMAP_HDQ_SYSCONFIG_SOFTRESET (1<<1)
> +#define OMAP_HDQ_SYSCONFIG_AUTOIDLE (1<<0)
> +#define OMAP_HDQ_SYSSTATUS 0x18
> +#define OMAP_HDQ_SYSSTATUS_RESETDONE (1<<0)
> +
> +#define OMAP_HDQ_FLAG_CLEAR 0
> +#define OMAP_HDQ_FLAG_SET 1
> +#define OMAP_HDQ_TIMEOUT (HZ/5)
> +
> +#define OMAP_HDQ_MAX_USER 4
> +
> +DECLARE_WAIT_QUEUE_HEAD(hdq_wait_queue);
> +int W1_ID;
> +
> +struct hdq_data {
> + resource_size_t hdq_base;
> + struct semaphore hdq_semlock;
> + int hdq_usecount;
> + struct clk *hdq_ick;
> + struct clk *hdq_fck;
> + u8 hdq_irqstatus;
> + spinlock_t hdq_spinlock;
> +};
> +
> +static struct hdq_data *hdq_data;
> +
> +static int __init omap_hdq_probe(struct platform_device *pdev);
> +static int omap_hdq_remove(struct platform_device *pdev);
> +
> +static struct platform_driver omap_hdq_driver = {
> + .probe = omap_hdq_probe,
> + .remove = omap_hdq_remove,
> + .suspend = NULL,
> + .resume = NULL,
> + .driver = {
> + .name = "omap_hdq",
> + },
> +};
> +
> +static u8 omap_w1_read_byte(void *data);
> +static void omap_w1_write_byte(void *data, u8 byte);
> +static u8 omap_w1_reset_bus(void *data);
> +static void omap_w1_search_bus(void *data, u8 search_type,
> + w1_slave_found_callback slave_found);
> +
> +static struct w1_bus_master omap_w1_master = {
> + .read_byte = omap_w1_read_byte,
> + .write_byte = omap_w1_write_byte,
> + .reset_bus = omap_w1_reset_bus,
> + .search = omap_w1_search_bus,
> +};
> +
> +/*
> + * HDQ register I/O routines
> + */
> +static inline u8
> +hdq_reg_in(u32 offset)
> +{
> + return omap_readb(hdq_data->hdq_base + offset);
> +}
> +
> +static inline u8
> +hdq_reg_out(u32 offset, u8 val)
> +{
> + omap_writeb(val, hdq_data->hdq_base + offset);
> + return val;
> +}
> +
> +static inline u8
> +hdq_reg_merge(u32 offset, u8 val, u8 mask)
> +{
> + u8 new_val = (omap_readb(hdq_data->hdq_base + offset) & ~mask)
> + | (val & mask);
> + omap_writeb(new_val, hdq_data->hdq_base + offset);
> + return new_val;
> +}
> +
> +/*
> + * Wait for one or more bits in flag change.
> + * HDQ_FLAG_SET: wait until any bit in the flag is set.
> + * HDQ_FLAG_CLEAR: wait until all bits in the flag are cleared.
> + * return 0 on success and -ETIMEOUT in the case of timeout.
> + */
s/-ETIMEOUT/-ETIMEDOUT
> +static int
> +hdq_wait_for_flag(u32 offset, u8 flag, u8 flag_set, u8 *status)
> +{
> + int ret = 0;
> + unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
> +
> + if (flag_set == OMAP_HDQ_FLAG_CLEAR) {
> + /* wait for the flag clear */
> + while (((*status = hdq_reg_in(offset)) & flag)
> + && time_before(jiffies, timeout)) {
> + set_current_state(TASK_UNINTERRUPTIBLE);
> + schedule_timeout(1);
> + }
> + if (unlikely(*status & flag))
> + ret = -ETIMEDOUT;
> + } else if (flag_set == OMAP_HDQ_FLAG_SET) {
> + /* wait for the flag set */
> + while (!((*status = hdq_reg_in(offset)) & flag)
> + && time_before(jiffies, timeout)) {
> + set_current_state(TASK_UNINTERRUPTIBLE);
> + schedule_timeout(1);
> + }
> + if (unlikely(!(*status & flag)))
> + ret = -ETIMEDOUT;
> + } else
> + return -EINVAL;
> +
> + return ret;
> +}
> +
> +/*
> + * write out a byte and fill *status with HDQ_INT_STATUS
> + */
> +static int
> +hdq_write_byte(u8 val, u8 *status)
> +{
> + int ret;
> + u8 tmp_status;
> + unsigned long irqflags;
> +
> + *status = 0;
> +
> + spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
> + /* clear interrupt flags via a dummy read */
> + hdq_reg_in(OMAP_HDQ_INT_STATUS);
> + /* ISR loads it with new INT_STATUS */
> + hdq_data->hdq_irqstatus = 0;
> + spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
> +
> + hdq_reg_out(OMAP_HDQ_TX_DATA, val);
> +
> + /* set the GO bit */
> + hdq_reg_merge(OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
> + OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
> + /* wait for the TXCOMPLETE bit */
> + ret = wait_event_interruptible_timeout(hdq_wait_queue,
> + hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
> + if (unlikely(ret < 0)) {
> + pr_debug("wait interrupted");
> + return -EINTR;
> + }
> +
> + spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
> + *status = hdq_data->hdq_irqstatus;
> + spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
> + /* check irqstatus */
> + if (!(*status & OMAP_HDQ_INT_STATUS_TXCOMPLETE)) {
> + pr_debug("timeout waiting for TXCOMPLETE/RXCOMPLETE, %x",
> + *status);
> + return -ETIMEDOUT;
> + }
> +
> + /* wait for the GO bit return to zero */
> + ret = hdq_wait_for_flag(OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
> + OMAP_HDQ_FLAG_CLEAR, &tmp_status);
> + if (ret) {
> + pr_debug("timeout waiting GO bit return to zero, %x",
> + tmp_status);
> + return ret;
> + }
> +
> + return ret;
> +}
> +
> +static irqreturn_t
> +hdq_isr(int irq, void *arg)
> +{
> + unsigned long irqflags;
> +
> + spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
> + hdq_data->hdq_irqstatus = hdq_reg_in(OMAP_HDQ_INT_STATUS);
> + spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
> + pr_debug("hdq_isr: %x", hdq_data->hdq_irqstatus);
> +
> + if (hdq_data->hdq_irqstatus &
> + (OMAP_HDQ_INT_STATUS_TXCOMPLETE | OMAP_HDQ_INT_STATUS_RXCOMPLETE
> + | OMAP_HDQ_INT_STATUS_TIMEOUT)) {
> + /* wake up sleeping process */
> + wake_up_interruptible(&hdq_wait_queue);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static u8 omap_w1_reset_bus(void *data)
> +{
> + return 0;
> +}
> +
> +static void omap_w1_search_bus(void *data, u8 search_type,
> + w1_slave_found_callback slave_found)
> +{
> + u64 module_id, rn_le, cs, id;
> +
> + if (W1_ID)
> + module_id = W1_ID;
> + else
> + module_id = 0x1;
> +
> + rn_le = cpu_to_le64(module_id);
> + /* HDQ might not obely truly the 1-wire spec.
> + * So calculate CRC based on module parameter.
> + */
> + cs = w1_calc_crc8((u8 *)&rn_le, 7);
> + id = (cs << 56) | module_id;
> +
> + slave_found(data, id);
> +}
> +
> +static int
> +_omap_hdq_reset(void)
> +{
> + int ret;
> + u8 tmp_status;
> +
> + hdq_reg_out(OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_SOFTRESET);
> + /*
> + * Select HDQ mode & enable clocks.
> + * It is observed that INT flags can't be cleared via a read and GO/INIT
> + * won't return to zero if interrupt is disabled. So we always enable
> + * interrupt.
> + */
> + hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
> + OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
> + OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
> +
> + /* wait for reset to complete */
> + ret = hdq_wait_for_flag(OMAP_HDQ_SYSSTATUS,
> + OMAP_HDQ_SYSSTATUS_RESETDONE, OMAP_HDQ_FLAG_SET, &tmp_status);
> + if (ret)
> + pr_debug("timeout waiting HDQ reset, %x", tmp_status);
> + else {
> + hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
> + OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
> + OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
> + hdq_reg_out(OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_AUTOIDLE);
> + }
> +
> + return ret;
> +}
> +
> +int
> +omap_hdq_reset(void)
> +{
> + int ret;
> +
> + ret = down_interruptible(&hdq_data->hdq_semlock);
> + if (ret < 0)
> + return -EINTR;
> +
> + if (!hdq_data->hdq_usecount) {
> + up(&hdq_data->hdq_semlock);
> + return -EINVAL;
> + }
> + ret = _omap_hdq_reset();
> + up(&hdq_data->hdq_semlock);
> + return ret;
> +}
> +
> +int
> +omap_hdq_break()
> +{
> + int ret;
> + u8 tmp_status;
> + unsigned long irqflags;
> +
> + ret = down_interruptible(&hdq_data->hdq_semlock);
> + if (ret < 0)
> + return -EINTR;
> +
> + if (!hdq_data->hdq_usecount) {
> + up(&hdq_data->hdq_semlock);
> + return -EINVAL;
> + }
> +
> + spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
> + /* clear interrupt flags via a dummy read */
> + hdq_reg_in(OMAP_HDQ_INT_STATUS);
> + /* ISR loads it with new INT_STATUS */
> + hdq_data->hdq_irqstatus = 0;
> + spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
> +
> + /* set the INIT and GO bit */
> + hdq_reg_merge(OMAP_HDQ_CTRL_STATUS,
> + OMAP_HDQ_CTRL_STATUS_INITIALIZATION | OMAP_HDQ_CTRL_STATUS_GO,
> + OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
> + OMAP_HDQ_CTRL_STATUS_GO);
> +
> + /* wait for the TIMEOUT bit */
> + ret = wait_event_interruptible_timeout(hdq_wait_queue,
> + hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
> + if (unlikely(ret < 0)) {
> + pr_debug("wait interrupted");
> + up(&hdq_data->hdq_semlock);
> + return -EINTR;
> + }
> +
> + spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
> + tmp_status = hdq_data->hdq_irqstatus;
> + spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
> + /* check irqstatus */
> + if (!(tmp_status & OMAP_HDQ_INT_STATUS_TIMEOUT)) {
> + pr_debug("timeout waiting for TIMEOUT, %x", tmp_status);
> + up(&hdq_data->hdq_semlock);
> + return -ETIMEDOUT;
> + }
> + /*
> + * wait for both INIT and GO bits rerurn to zero.
> + * zero wait time expected for interrupt mode.
> + */
> + ret = hdq_wait_for_flag(OMAP_HDQ_CTRL_STATUS,
> + OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
> + OMAP_HDQ_CTRL_STATUS_GO, OMAP_HDQ_FLAG_CLEAR,
> + &tmp_status);
> + if (ret)
> + pr_debug("timeout waiting INIT&GO bits return to zero, %x",
> + tmp_status);
> +
> + up(&hdq_data->hdq_semlock);
> + return ret;
> +}
> +EXPORT_SYMBOL(omap_hdq_break);
> +
> +int hdq_read_byte(u8 *val)
> +{
> + int ret;
> + u8 status;
> + unsigned long irqflags;
> +
> + ret = down_interruptible(&hdq_data->hdq_semlock);
> + if (ret < 0)
> + return -EINTR;
> +
> + if (!hdq_data->hdq_usecount) {
> + up(&hdq_data->hdq_semlock);
> + return -EINVAL;
> + }
> +
> + if (!(hdq_data->hdq_irqstatus & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
> + hdq_reg_merge(OMAP_HDQ_CTRL_STATUS,
> + OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO,
> + OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
> + /*
> + * The RX comes immediately after TX. It
> + * triggers another interrupt before we
> + * sleep. So we have to wait for RXCOMPLETE bit.
> + */
> + {
> + unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
> + while (!(hdq_data->hdq_irqstatus
> + & OMAP_HDQ_INT_STATUS_RXCOMPLETE)
> + && time_before(jiffies, timeout)) {
> + set_current_state(TASK_UNINTERRUPTIBLE);
> + schedule_timeout(1);
> + }
> + }
> + hdq_reg_merge(OMAP_HDQ_CTRL_STATUS, 0,
> + OMAP_HDQ_CTRL_STATUS_DIR);
> + spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
> + status = hdq_data->hdq_irqstatus;
> + spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
> + /* check irqstatus */
> + if (!(status & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
> + pr_debug("timeout waiting for RXCOMPLETE, %x", status);
> + up(&hdq_data->hdq_semlock);
> + return -ETIMEDOUT;
> + }
> + }
> + /* the data is ready. Read it in! */
> + *val = hdq_reg_in(OMAP_HDQ_RX_DATA);
> + up(&hdq_data->hdq_semlock);
> +
> + return 0;
> +
> +}
> +
> +int
> +omap_hdq_get()
> +{
> + int ret = 0;
> +
> + ret = down_interruptible(&hdq_data->hdq_semlock);
> + if (ret < 0)
> + return -EINTR;
> +
> + if (OMAP_HDQ_MAX_USER == hdq_data->hdq_usecount) {
> + pr_debug("attempt to exceed the max use count");
> + up(&hdq_data->hdq_semlock);
> + ret = -EINVAL;
> + } else {
> + hdq_data->hdq_usecount++;
> + try_module_get(THIS_MODULE);
> + if (1 == hdq_data->hdq_usecount) {
> + if (clk_enable(hdq_data->hdq_ick)) {
> + pr_debug("Can not enable ick\n");
> + clk_put(hdq_data->hdq_ick);
> + clk_put(hdq_data->hdq_fck);
> + up(&hdq_data->hdq_semlock);
> + return -ENODEV;
> + }
> + if (clk_enable(hdq_data->hdq_fck)) {
> + pr_debug("Can not enable fck\n");
> + clk_put(hdq_data->hdq_ick);
> + clk_put(hdq_data->hdq_fck);
> + up(&hdq_data->hdq_semlock);
> + return -ENODEV;
> + }
> +
> + /* make sure HDQ is out of reset */
> + if (!(hdq_reg_in(OMAP_HDQ_SYSSTATUS) &
> + OMAP_HDQ_SYSSTATUS_RESETDONE)) {
> + ret = _omap_hdq_reset();
> + if (ret)
> + /* back up the count */
> + hdq_data->hdq_usecount--;
> + } else {
> + /* select HDQ mode & enable clocks */
> + hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
> + OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
> + OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
> + hdq_reg_out(OMAP_HDQ_SYSCONFIG,
> + OMAP_HDQ_SYSCONFIG_AUTOIDLE);
> + hdq_reg_in(OMAP_HDQ_INT_STATUS);
> + }
> + }
> + }
> + up(&hdq_data->hdq_semlock);
> + return ret;
> +}
> +EXPORT_SYMBOL(omap_hdq_get);
> +
> +int
> +omap_hdq_put()
> +{
> + int ret = 0;
> +
> + ret = down_interruptible(&hdq_data->hdq_semlock);
> + if (ret < 0)
> + return -EINTR;
> +
> + if (0 == hdq_data->hdq_usecount) {
> + pr_debug("attempt to decrement use count when it is zero");
> + ret = -EINVAL;
> + } else {
> + hdq_data->hdq_usecount--;
> + module_put(THIS_MODULE);
> + if (0 == hdq_data->hdq_usecount) {
> + clk_disable(hdq_data->hdq_ick);
> + clk_disable(hdq_data->hdq_fck);
> + }
> + }
> + up(&hdq_data->hdq_semlock);
> + return ret;
> +}
> +EXPORT_SYMBOL(omap_hdq_put);
> +
> +static u8 omap_w1_read_byte(void *data)
> +{
> + u8 val;
> + int ret;
> +
> + ret = hdq_read_byte(&val);
> + if (ret)
> + return -1;
> + return val;
> +}
> +
> +static void omap_w1_write_byte(void *data, u8 byte)
> +{
> + u8 status;
> +
> + hdq_write_byte(byte, &status);
> + pr_debug("Ctrl status %x\n", status);
> + return;
> +}
> +
> +static int __init omap_hdq_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + int ret, irq;
> + u8 rev;
> +
> + if (!pdev)
> + return -ENODEV;
> +
> + hdq_data = kmalloc(sizeof(*hdq_data), GFP_KERNEL);
> + if (!hdq_data)
> + return -ENODEV;
> +
> + platform_set_drvdata(pdev, hdq_data);
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (res == NULL) {
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> + return -ENXIO;
> + }
> +
> + hdq_data->hdq_base = res->start;
> +
> + /* get interface & functional clock objects */
> + hdq_data->hdq_ick = clk_get(&pdev->dev, "hdq_ick");
> + hdq_data->hdq_fck = clk_get(&pdev->dev, "hdq_fck");
> +
> + if (IS_ERR(hdq_data->hdq_ick) || IS_ERR(hdq_data->hdq_fck)) {
> + pr_debug("Can't get HDQ clock objects\n");
> + if (IS_ERR(hdq_data->hdq_ick)) {
> + ret = PTR_ERR(hdq_data->hdq_ick);
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> + return ret;
> + }
> + if (IS_ERR(hdq_data->hdq_fck)) {
> + ret = PTR_ERR(hdq_data->hdq_fck);
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> + return ret;
> + }
> + }
> +
> + hdq_data->hdq_usecount = 0;
> + sema_init(&hdq_data->hdq_semlock, 1);
> +
> + if (clk_enable(hdq_data->hdq_ick)) {
> + pr_debug("Can not enable ick\n");
> + clk_put(hdq_data->hdq_ick);
> + clk_put(hdq_data->hdq_fck);
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> + return -ENODEV;
> + }
> +
> + rev = hdq_reg_in(OMAP_HDQ_REVISION);
> + pr_info("OMAP HDQ Hardware Revision %c.%c. Driver in %s mode.\n",
> + (rev >> 4) + '0', (rev & 0x0f) + '0', "Interrupt");
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0) {
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> + return -ENXIO;
> + }
> +
> + if (request_irq(irq, hdq_isr, IRQF_DISABLED, "OMAP HDQ",
> + &hdq_data->hdq_semlock)) {
> + pr_debug("request_irq failed\n");
> + clk_disable(hdq_data->hdq_ick);
> + clk_put(hdq_data->hdq_ick);
> + clk_put(hdq_data->hdq_fck);
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> + return -ENODEV;
> + }
> + spin_lock_init(&hdq_data->hdq_spinlock);
> + /* don't clock the HDQ until it is needed */
> + clk_disable(hdq_data->hdq_ick);
> +
> + ret = w1_add_master_device(&omap_w1_master);
> + if (ret) {
> + pr_debug("Failure in registering w1 master\n");
> + clk_put(hdq_data->hdq_ick);
> + clk_put(hdq_data->hdq_fck);
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int omap_hdq_remove(struct platform_device *pdev)
> +{
> + down_interruptible(&hdq_data->hdq_semlock);
> + if (0 != hdq_data->hdq_usecount) {
> + pr_debug("removed when use count is not zero\n");
> + return -EBUSY;
> + }
> + up(&hdq_data->hdq_semlock);
> +
> + /* remove module dependency */
> + clk_put(hdq_data->hdq_ick);
> + clk_put(hdq_data->hdq_fck);
> + free_irq(INT_24XX_HDQ_IRQ, &hdq_data->hdq_semlock);
> + platform_set_drvdata(pdev, NULL);
> + kfree(hdq_data);
> +
> + return 0;
> +}
> +
> +static int __init
> +omap_hdq_init(void)
> +{
> + return platform_driver_register(&omap_hdq_driver);
> +}
> +
> +static void __exit
> +omap_hdq_exit(void)
> +{
> + platform_driver_unregister(&omap_hdq_driver);
> +}
> +
> +module_init(omap_hdq_init);
> +module_exit(omap_hdq_exit);
> +
> +module_param(W1_ID, int, S_IRUSR);
> +
> +MODULE_AUTHOR("Texas Instruments");
> +MODULE_DESCRIPTION("HDQ driver Library");
> +MODULE_LICENSE("GPL");
> Index: linux-omap-hdq-new/drivers/w1/masters/Kconfig
> ===================================================================
> --- linux-omap-hdq-new.orig/drivers/w1/masters/Kconfig 2007-11-27 20:04:44.000000000 +0530
> +++ linux-omap-hdq-new/drivers/w1/masters/Kconfig 2007-12-04 17:58:44.000000000 +0530
> @@ -42,5 +42,13 @@
> in HP iPAQ devices like h5xxx, h2200, and ASIC3-based like
> hx4700.
>
> +config HDQ_MASTER_OMAP
> + tristate "OMAP HDQ driver"
> + depends on ARCH_OMAP2430 || ARCH_OMAP34XX
> + help
> + Say Y here if you want support for the 1-wire or HDQ Interface
> + on an OMAP processor.
> +
> +
> endmenu
>
> Index: linux-omap-hdq-new/drivers/w1/masters/Makefile
> ===================================================================
> --- linux-omap-hdq-new.orig/drivers/w1/masters/Makefile 2007-11-27 20:04:44.000000000 +0530
> +++ linux-omap-hdq-new/drivers/w1/masters/Makefile 2007-12-04 08:55:21.000000000 +0530
> @@ -6,3 +6,4 @@
> obj-$(CONFIG_W1_MASTER_DS2490) += ds2490.o
> obj-$(CONFIG_W1_MASTER_DS2482) += ds2482.o
> obj-$(CONFIG_W1_MASTER_DS1WM) += ds1wm.o
> +obj-$(CONFIG_HDQ_MASTER_OMAP) += omap_hdq.o
> Index: linux-omap-hdq-new/include/asm-arm/arch-omap/hdq.h
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux-omap-hdq-new/include/asm-arm/arch-omap/hdq.h 2007-12-04 08:55:21.000000000 +0530
> @@ -0,0 +1,23 @@
> +/*
> + * include/asm-arm/arch-omap2/hdq.h
OMAP GIT tree doesn't have arch-omap2 directory.
> + *
> + * Copyright (C) 2006-2007 Texas Instruments, Inc.
> + *
> + * This file is licensed under the terms of the GNU General Public License
> + * version 2. This program is licensed "as is" without any warranty of any
> + * kind, whether express or implied.
> + *
> + */
> +
> +#ifndef __ASM_OMAP2_HDQ_H__
> +#define __ASM_OMAP2_HDQ_H__
> +
> +/* Note the following API has to be called in a process context */
> +
> +int omap_hdq_get(void); /* request the HDQ block */
> +int omap_hdq_put(void); /* release the HDQ block */
> +
> +int omap_hdq_reset(void); /* reset the HDQ block */
> +int omap_hdq_break(void); /* reset the slave by sending it a break pulse */
> +
> +#endif
>
>
> _______________________________________________
> Linux-omap-open-source mailing list
> Linux-omap-open-source@linux.omap.com
> http://linux.omap.com/mailman/listinfo/linux-omap-open-source
>
--
--Trilok Soni
^ permalink raw reply [flat|nested] 3+ messages in thread
* [RFC/PATCH 2/5] HDQ/1-wire support for OMAP2430/3430
@ 2007-12-12 6:37 Madhusudhan Chikkature Rajashekar
0 siblings, 0 replies; 3+ messages in thread
From: Madhusudhan Chikkature Rajashekar @ 2007-12-12 6:37 UTC (permalink / raw)
To: linux-omap-open-source; +Cc: 'Evgeniy Polyakov', linux-omap
Hi Tony,
I am reposting the patch after fixing the comments provided by Trilok Soni.
Thanks,
Madhu
-------------------------------------------------------------------------------------
This patch adds OMAP2430/3430 HDQ/1-Wire driver support.
Signed-off-by: Madhusudhan Chikkature<madhu.cr@ti.com>
---
drivers/w1/masters/Kconfig | 8
drivers/w1/masters/Makefile | 1
drivers/w1/masters/omap_hdq.c | 654 ++++++++++++++++++++++++++++++++++++++++
include/asm-arm/arch-omap/hdq.h | 23 +
4 files changed, 686 insertions(+)
Index: linux-omap-2.6/drivers/w1/masters/omap_hdq.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-omap-2.6/drivers/w1/masters/omap_hdq.c 2007-12-12 09:36:22.094565740 +0530
@@ -0,0 +1,654 @@
+/*
+ * drivers/w1/masters/omap_hdq.c
+ *
+ * Copyright (C) 2007 Texas Instruments, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <asm/irq.h>
+#include <asm/hardware.h>
+#include <asm/arch/hdq.h>
+
+#include "../w1.h"
+#include "../w1_int.h"
+
+#define MOD_NAME "OMAP_HDQ:"
+
+#define OMAP_HDQ_REVISION 0x00
+#define OMAP_HDQ_TX_DATA 0x04
+#define OMAP_HDQ_RX_DATA 0x08
+#define OMAP_HDQ_CTRL_STATUS 0x0c
+#define OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK (1<<6)
+#define OMAP_HDQ_CTRL_STATUS_CLOCKENABLE (1<<5)
+#define OMAP_HDQ_CTRL_STATUS_GO (1<<4)
+#define OMAP_HDQ_CTRL_STATUS_INITIALIZATION (1<<2)
+#define OMAP_HDQ_CTRL_STATUS_DIR (1<<1)
+#define OMAP_HDQ_CTRL_STATUS_MODE (1<<0)
+#define OMAP_HDQ_INT_STATUS 0x10
+#define OMAP_HDQ_INT_STATUS_TXCOMPLETE (1<<2)
+#define OMAP_HDQ_INT_STATUS_RXCOMPLETE (1<<1)
+#define OMAP_HDQ_INT_STATUS_TIMEOUT (1<<0)
+#define OMAP_HDQ_SYSCONFIG 0x14
+#define OMAP_HDQ_SYSCONFIG_SOFTRESET (1<<1)
+#define OMAP_HDQ_SYSCONFIG_AUTOIDLE (1<<0)
+#define OMAP_HDQ_SYSSTATUS 0x18
+#define OMAP_HDQ_SYSSTATUS_RESETDONE (1<<0)
+
+#define OMAP_HDQ_FLAG_CLEAR 0
+#define OMAP_HDQ_FLAG_SET 1
+#define OMAP_HDQ_TIMEOUT (HZ/5)
+
+#define OMAP_HDQ_MAX_USER 4
+
+DECLARE_WAIT_QUEUE_HEAD(hdq_wait_queue);
+int W1_ID;
+
+struct hdq_data {
+ resource_size_t hdq_base;
+ struct semaphore hdq_semlock;
+ int hdq_usecount;
+ struct clk *hdq_ick;
+ struct clk *hdq_fck;
+ u8 hdq_irqstatus;
+ spinlock_t hdq_spinlock;
+};
+
+static struct hdq_data *hdq_data;
+
+static int __init omap_hdq_probe(struct platform_device *pdev);
+static int omap_hdq_remove(struct platform_device *pdev);
+
+static struct platform_driver omap_hdq_driver = {
+ .probe = omap_hdq_probe,
+ .remove = omap_hdq_remove,
+ .suspend = NULL,
+ .resume = NULL,
+ .driver = {
+ .name = "omap_hdq",
+ },
+};
+
+static u8 omap_w1_read_byte(void *data);
+static void omap_w1_write_byte(void *data, u8 byte);
+static u8 omap_w1_reset_bus(void *data);
+static void omap_w1_search_bus(void *data, u8 search_type,
+ w1_slave_found_callback slave_found);
+
+static struct w1_bus_master omap_w1_master = {
+ .read_byte = omap_w1_read_byte,
+ .write_byte = omap_w1_write_byte,
+ .reset_bus = omap_w1_reset_bus,
+ .search = omap_w1_search_bus,
+};
+
+/*
+ * HDQ register I/O routines
+ */
+static inline u8
+hdq_reg_in(u32 offset)
+{
+ return omap_readb(hdq_data->hdq_base + offset);
+}
+
+static inline u8
+hdq_reg_out(u32 offset, u8 val)
+{
+ omap_writeb(val, hdq_data->hdq_base + offset);
+ return val;
+}
+
+static inline u8
+hdq_reg_merge(u32 offset, u8 val, u8 mask)
+{
+ u8 new_val = (omap_readb(hdq_data->hdq_base + offset) & ~mask)
+ | (val & mask);
+ omap_writeb(new_val, hdq_data->hdq_base + offset);
+ return new_val;
+}
+
+/*
+ * Wait for one or more bits in flag change.
+ * HDQ_FLAG_SET: wait until any bit in the flag is set.
+ * HDQ_FLAG_CLEAR: wait until all bits in the flag are cleared.
+ * return 0 on success and -ETIMEDOUT in the case of timeout.
+ */
+static int
+hdq_wait_for_flag(u32 offset, u8 flag, u8 flag_set, u8 *status)
+{
+ int ret = 0;
+ unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
+
+ if (flag_set == OMAP_HDQ_FLAG_CLEAR) {
+ /* wait for the flag clear */
+ while (((*status = hdq_reg_in(offset)) & flag)
+ && time_before(jiffies, timeout)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+ if (unlikely(*status & flag))
+ ret = -ETIMEDOUT;
+ } else if (flag_set == OMAP_HDQ_FLAG_SET) {
+ /* wait for the flag set */
+ while (!((*status = hdq_reg_in(offset)) & flag)
+ && time_before(jiffies, timeout)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+ if (unlikely(!(*status & flag)))
+ ret = -ETIMEDOUT;
+ } else
+ return -EINVAL;
+
+ return ret;
+}
+
+/*
+ * write out a byte and fill *status with HDQ_INT_STATUS
+ */
+static int
+hdq_write_byte(u8 val, u8 *status)
+{
+ int ret;
+ u8 tmp_status;
+ unsigned long irqflags;
+
+ *status = 0;
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ /* clear interrupt flags via a dummy read */
+ hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ /* ISR loads it with new INT_STATUS */
+ hdq_data->hdq_irqstatus = 0;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+
+ hdq_reg_out(OMAP_HDQ_TX_DATA, val);
+
+ /* set the GO bit */
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
+ /* wait for the TXCOMPLETE bit */
+ ret = wait_event_interruptible_timeout(hdq_wait_queue,
+ hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
+ if (unlikely(ret < 0)) {
+ pr_debug("wait interrupted");
+ return -EINTR;
+ }
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ *status = hdq_data->hdq_irqstatus;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ /* check irqstatus */
+ if (!(*status & OMAP_HDQ_INT_STATUS_TXCOMPLETE)) {
+ pr_debug("timeout waiting for TXCOMPLETE/RXCOMPLETE, %x",
+ *status);
+ return -ETIMEDOUT;
+ }
+
+ /* wait for the GO bit return to zero */
+ ret = hdq_wait_for_flag(OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_FLAG_CLEAR, &tmp_status);
+ if (ret) {
+ pr_debug("timeout waiting GO bit return to zero, %x",
+ tmp_status);
+ return ret;
+ }
+
+ return ret;
+}
+
+static irqreturn_t
+hdq_isr(int irq, void *arg)
+{
+ unsigned long irqflags;
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ hdq_data->hdq_irqstatus = hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ pr_debug("hdq_isr: %x", hdq_data->hdq_irqstatus);
+
+ if (hdq_data->hdq_irqstatus &
+ (OMAP_HDQ_INT_STATUS_TXCOMPLETE | OMAP_HDQ_INT_STATUS_RXCOMPLETE
+ | OMAP_HDQ_INT_STATUS_TIMEOUT)) {
+ /* wake up sleeping process */
+ wake_up_interruptible(&hdq_wait_queue);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static u8 omap_w1_reset_bus(void *data)
+{
+ return 0;
+}
+
+static void omap_w1_search_bus(void *data, u8 search_type,
+ w1_slave_found_callback slave_found)
+{
+ u64 module_id, rn_le, cs, id;
+
+ if (W1_ID)
+ module_id = W1_ID;
+ else
+ module_id = 0x1;
+
+ rn_le = cpu_to_le64(module_id);
+ /*
+ * HDQ might not obey truly the 1-wire spec.
+ * So calculate CRC based on module parameter.
+ */
+ cs = w1_calc_crc8((u8 *)&rn_le, 7);
+ id = (cs << 56) | module_id;
+
+ slave_found(data, id);
+}
+
+static int
+_omap_hdq_reset(void)
+{
+ int ret;
+ u8 tmp_status;
+
+ hdq_reg_out(OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_SOFTRESET);
+ /*
+ * Select HDQ mode & enable clocks.
+ * It is observed that INT flags can't be cleared via a read and GO/INIT
+ * won't return to zero if interrupt is disabled. So we always enable
+ * interrupt.
+ */
+ hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
+ OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
+
+ /* wait for reset to complete */
+ ret = hdq_wait_for_flag(OMAP_HDQ_SYSSTATUS,
+ OMAP_HDQ_SYSSTATUS_RESETDONE, OMAP_HDQ_FLAG_SET, &tmp_status);
+ if (ret)
+ pr_debug("timeout waiting HDQ reset, %x", tmp_status);
+ else {
+ hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
+ OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
+ hdq_reg_out(OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_AUTOIDLE);
+ }
+
+ return ret;
+}
+
+int
+omap_hdq_reset(void)
+{
+ int ret;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (!hdq_data->hdq_usecount) {
+ up(&hdq_data->hdq_semlock);
+ return -EINVAL;
+ }
+ ret = _omap_hdq_reset();
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+
+int
+omap_hdq_break()
+{
+ int ret;
+ u8 tmp_status;
+ unsigned long irqflags;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (!hdq_data->hdq_usecount) {
+ up(&hdq_data->hdq_semlock);
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ /* clear interrupt flags via a dummy read */
+ hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ /* ISR loads it with new INT_STATUS */
+ hdq_data->hdq_irqstatus = 0;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+
+ /* set the INIT and GO bit */
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_INITIALIZATION | OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
+ OMAP_HDQ_CTRL_STATUS_GO);
+
+ /* wait for the TIMEOUT bit */
+ ret = wait_event_interruptible_timeout(hdq_wait_queue,
+ hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
+ if (unlikely(ret < 0)) {
+ pr_debug("wait interrupted");
+ up(&hdq_data->hdq_semlock);
+ return -EINTR;
+ }
+
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ tmp_status = hdq_data->hdq_irqstatus;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ /* check irqstatus */
+ if (!(tmp_status & OMAP_HDQ_INT_STATUS_TIMEOUT)) {
+ pr_debug("timeout waiting for TIMEOUT, %x", tmp_status);
+ up(&hdq_data->hdq_semlock);
+ return -ETIMEDOUT;
+ }
+ /*
+ * wait for both INIT and GO bits rerurn to zero.
+ * zero wait time expected for interrupt mode.
+ */
+ ret = hdq_wait_for_flag(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
+ OMAP_HDQ_CTRL_STATUS_GO, OMAP_HDQ_FLAG_CLEAR,
+ &tmp_status);
+ if (ret)
+ pr_debug("timeout waiting INIT&GO bits return to zero, %x",
+ tmp_status);
+
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_hdq_break);
+
+int hdq_read_byte(u8 *val)
+{
+ int ret;
+ u8 status;
+ unsigned long irqflags;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (!hdq_data->hdq_usecount) {
+ up(&hdq_data->hdq_semlock);
+ return -EINVAL;
+ }
+
+ if (!(hdq_data->hdq_irqstatus & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO,
+ OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
+ /*
+ * The RX comes immediately after TX. It
+ * triggers another interrupt before we
+ * sleep. So we have to wait for RXCOMPLETE bit.
+ */
+ {
+ unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
+ while (!(hdq_data->hdq_irqstatus
+ & OMAP_HDQ_INT_STATUS_RXCOMPLETE)
+ && time_before(jiffies, timeout)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+ }
+ hdq_reg_merge(OMAP_HDQ_CTRL_STATUS, 0,
+ OMAP_HDQ_CTRL_STATUS_DIR);
+ spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
+ status = hdq_data->hdq_irqstatus;
+ spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
+ /* check irqstatus */
+ if (!(status & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
+ pr_debug("timeout waiting for RXCOMPLETE, %x", status);
+ up(&hdq_data->hdq_semlock);
+ return -ETIMEDOUT;
+ }
+ }
+ /* the data is ready. Read it in! */
+ *val = hdq_reg_in(OMAP_HDQ_RX_DATA);
+ up(&hdq_data->hdq_semlock);
+
+ return 0;
+
+}
+
+int
+omap_hdq_get()
+{
+ int ret = 0;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (OMAP_HDQ_MAX_USER == hdq_data->hdq_usecount) {
+ pr_debug("attempt to exceed the max use count");
+ up(&hdq_data->hdq_semlock);
+ ret = -EINVAL;
+ } else {
+ hdq_data->hdq_usecount++;
+ try_module_get(THIS_MODULE);
+ if (1 == hdq_data->hdq_usecount) {
+ if (clk_enable(hdq_data->hdq_ick)) {
+ pr_debug("Can not enable ick\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ up(&hdq_data->hdq_semlock);
+ return -ENODEV;
+ }
+ if (clk_enable(hdq_data->hdq_fck)) {
+ pr_debug("Can not enable fck\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ up(&hdq_data->hdq_semlock);
+ return -ENODEV;
+ }
+
+ /* make sure HDQ is out of reset */
+ if (!(hdq_reg_in(OMAP_HDQ_SYSSTATUS) &
+ OMAP_HDQ_SYSSTATUS_RESETDONE)) {
+ ret = _omap_hdq_reset();
+ if (ret)
+ /* back up the count */
+ hdq_data->hdq_usecount--;
+ } else {
+ /* select HDQ mode & enable clocks */
+ hdq_reg_out(OMAP_HDQ_CTRL_STATUS,
+ OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
+ OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK);
+ hdq_reg_out(OMAP_HDQ_SYSCONFIG,
+ OMAP_HDQ_SYSCONFIG_AUTOIDLE);
+ hdq_reg_in(OMAP_HDQ_INT_STATUS);
+ }
+ }
+ }
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_hdq_get);
+
+int
+omap_hdq_put()
+{
+ int ret = 0;
+
+ ret = down_interruptible(&hdq_data->hdq_semlock);
+ if (ret < 0)
+ return -EINTR;
+
+ if (0 == hdq_data->hdq_usecount) {
+ pr_debug("attempt to decrement use count when it is zero");
+ ret = -EINVAL;
+ } else {
+ hdq_data->hdq_usecount--;
+ module_put(THIS_MODULE);
+ if (0 == hdq_data->hdq_usecount) {
+ clk_disable(hdq_data->hdq_ick);
+ clk_disable(hdq_data->hdq_fck);
+ }
+ }
+ up(&hdq_data->hdq_semlock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_hdq_put);
+
+static u8 omap_w1_read_byte(void *data)
+{
+ u8 val;
+ int ret;
+
+ ret = hdq_read_byte(&val);
+ if (ret)
+ return -1;
+ return val;
+}
+
+static void omap_w1_write_byte(void *data, u8 byte)
+{
+ u8 status;
+
+ hdq_write_byte(byte, &status);
+ pr_debug("Ctrl status %x\n", status);
+ return;
+}
+
+static int __init omap_hdq_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ int ret, irq;
+ u8 rev;
+
+ if (!pdev)
+ return -ENODEV;
+
+ hdq_data = kmalloc(sizeof(*hdq_data), GFP_KERNEL);
+ if (!hdq_data)
+ return -ENODEV;
+
+ platform_set_drvdata(pdev, hdq_data);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENXIO;
+ }
+
+ hdq_data->hdq_base = res->start;
+
+ /* get interface & functional clock objects */
+ hdq_data->hdq_ick = clk_get(&pdev->dev, "hdq_ick");
+ hdq_data->hdq_fck = clk_get(&pdev->dev, "hdq_fck");
+
+ if (IS_ERR(hdq_data->hdq_ick) || IS_ERR(hdq_data->hdq_fck)) {
+ pr_debug("Can't get HDQ clock objects\n");
+ if (IS_ERR(hdq_data->hdq_ick)) {
+ ret = PTR_ERR(hdq_data->hdq_ick);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return ret;
+ }
+ if (IS_ERR(hdq_data->hdq_fck)) {
+ ret = PTR_ERR(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return ret;
+ }
+ }
+
+ hdq_data->hdq_usecount = 0;
+ sema_init(&hdq_data->hdq_semlock, 1);
+
+ if (clk_enable(hdq_data->hdq_ick)) {
+ pr_debug("Can not enable ick\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENODEV;
+ }
+
+ rev = hdq_reg_in(OMAP_HDQ_REVISION);
+ pr_info("OMAP HDQ Hardware Revision %c.%c. Driver in %s mode.\n",
+ (rev >> 4) + '0', (rev & 0x0f) + '0', "Interrupt");
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENXIO;
+ }
+
+ if (request_irq(irq, hdq_isr, IRQF_DISABLED, "OMAP HDQ",
+ &hdq_data->hdq_semlock)) {
+ pr_debug("request_irq failed\n");
+ clk_disable(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return -ENODEV;
+ }
+ spin_lock_init(&hdq_data->hdq_spinlock);
+ /* don't clock the HDQ until it is needed */
+ clk_disable(hdq_data->hdq_ick);
+
+ ret = w1_add_master_device(&omap_w1_master);
+ if (ret) {
+ pr_debug("Failure in registering w1 master\n");
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int omap_hdq_remove(struct platform_device *pdev)
+{
+ down_interruptible(&hdq_data->hdq_semlock);
+ if (0 != hdq_data->hdq_usecount) {
+ pr_debug("removed when use count is not zero\n");
+ return -EBUSY;
+ }
+ up(&hdq_data->hdq_semlock);
+
+ /* remove module dependency */
+ clk_put(hdq_data->hdq_ick);
+ clk_put(hdq_data->hdq_fck);
+ free_irq(INT_24XX_HDQ_IRQ, &hdq_data->hdq_semlock);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hdq_data);
+
+ return 0;
+}
+
+static int __init
+omap_hdq_init(void)
+{
+ return platform_driver_register(&omap_hdq_driver);
+}
+
+static void __exit
+omap_hdq_exit(void)
+{
+ platform_driver_unregister(&omap_hdq_driver);
+}
+
+module_init(omap_hdq_init);
+module_exit(omap_hdq_exit);
+
+module_param(W1_ID, int, S_IRUSR);
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("HDQ driver Library");
+MODULE_LICENSE("GPL");
Index: linux-omap-2.6/drivers/w1/masters/Kconfig
===================================================================
--- linux-omap-2.6.orig/drivers/w1/masters/Kconfig 2007-12-11 13:53:22.675333323 +0530
+++ linux-omap-2.6/drivers/w1/masters/Kconfig 2007-12-11 14:00:05.692489991 +0530
@@ -42,5 +42,13 @@
in HP iPAQ devices like h5xxx, h2200, and ASIC3-based like
hx4700.
+config HDQ_MASTER_OMAP
+ tristate "OMAP HDQ driver"
+ depends on ARCH_OMAP2430 || ARCH_OMAP34XX
+ help
+ Say Y here if you want support for the 1-wire or HDQ Interface
+ on an OMAP processor.
+
+
endmenu
Index: linux-omap-2.6/drivers/w1/masters/Makefile
===================================================================
--- linux-omap-2.6.orig/drivers/w1/masters/Makefile 2007-12-11 13:53:22.675333323 +0530
+++ linux-omap-2.6/drivers/w1/masters/Makefile 2007-12-11 14:00:05.692489991 +0530
@@ -6,3 +6,4 @@
obj-$(CONFIG_W1_MASTER_DS2490) += ds2490.o
obj-$(CONFIG_W1_MASTER_DS2482) += ds2482.o
obj-$(CONFIG_W1_MASTER_DS1WM) += ds1wm.o
+obj-$(CONFIG_HDQ_MASTER_OMAP) += omap_hdq.o
Index: linux-omap-2.6/include/asm-arm/arch-omap/hdq.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-omap-2.6/include/asm-arm/arch-omap/hdq.h 2007-12-12 09:37:05.224191812 +0530
@@ -0,0 +1,23 @@
+/*
+ * include/asm-arm/arch-omap/hdq.h
+ *
+ * Copyright (C) 2006-2007 Texas Instruments, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ */
+
+#ifndef __ASM_OMAP2_HDQ_H__
+#define __ASM_OMAP2_HDQ_H__
+
+/* Note the following API has to be called in a process context */
+
+int omap_hdq_get(void); /* request the HDQ block */
+int omap_hdq_put(void); /* release the HDQ block */
+
+int omap_hdq_reset(void); /* reset the HDQ block */
+int omap_hdq_break(void); /* reset the slave by sending it a break pulse */
+
+#endif
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2007-12-12 6:37 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2007-12-10 10:17 [RFC/PATCH 2/5] HDQ/1-wire support for OMAP2430/3430 Madhusudhan Chikkature Rajashekar
2007-12-11 11:20 ` Trilok Soni
-- strict thread matches above, loose matches on Subject: below --
2007-12-12 6:37 Madhusudhan Chikkature Rajashekar
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