[PATCH] i2c: QUP based bus driver for Qualcomm MSM chipsets

Kenneth Heitke
2010-07-23T02:47:49Z

This bus driver supports the QUP i2c hardware controller in the Qualcomm
MSM SOCs. The Qualcomm Universal Peripheral Engine (QUP) is a general
purpose data path engine with input/output FIFOs and an embedded i2c
mini-core. The driver supports FIFO mode (for low bandwidth applications)
and block mode (interrupt generated for each block-size data transfer).
The driver currently does not support DMA transfers.

Signed-off-by: Kenneth Heitke <kheitke@codeaurora.org>
---
drivers/i2c/busses/Kconfig | 12 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-qup.c | 1080 ++++++++++++++++++++++++++++++++++++++++++
include/linux/i2c-msm.h | 29 ++
4 files changed, 1122 insertions(+), 0 deletions(-)
create mode 100644 drivers/i2c/busses/i2c-qup.c
create mode 100644 include/linux/i2c-msm.h

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index bceafbf..03d8f8f 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -521,6 +521,18 @@ config I2C_PXA_SLAVE
is necessary for systems where the PXA may be a target on the
I2C bus.

+config I2C_QUP
+ tristate "Qualcomm MSM QUP I2C Controller"
+ depends on I2C && HAVE_CLK && (ARCH_MSM7X30 || ARCH_MSM8X60 || \
+ (ARCH_QSD8X50 && MSM_SOC_REV_A))
+ help
+ If you say yes to this option, support will be included for the
+ built-in QUP I2C interface on Qualcomm MSM family processors.
+
+ The Qualcomm Universal Peripheral Engine (QUP) is a general
+ purpose data path engine with input/output FIFOs and an
+ embedded I2C mini-core.
+
config I2C_S3C2410
tristate "S3C2410 I2C Driver"
depends on ARCH_S3C2410 || ARCH_S3C64XX
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 936880b..6a52572 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_I2C_PCA_PLATFORM) += i2c-pca-platform.o
obj-$(CONFIG_I2C_PMCMSP) += i2c-pmcmsp.o
obj-$(CONFIG_I2C_PNX) += i2c-pnx.o
obj-$(CONFIG_I2C_PXA) += i2c-pxa.o
+obj-$(CONFIG_I2C_QUP) += i2c-qup.o
obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o
obj-$(CONFIG_I2C_S6000) += i2c-s6000.o
obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o
diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
new file mode 100644
index 0000000..3d7abab
--- /dev/null
+++ b/drivers/i2c/busses/i2c-qup.c
@@ -0,0 +1,1080 @@
+/* Copyright (c) 2009-2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ */
+/*
+ * QUP driver for Qualcomm MSM platforms
+ *
+ */
+
+/* #define DEBUG */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/timer.h>
+#include <linux/i2c-msm.h>
+
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION("0.2");
+MODULE_ALIAS("platform:i2c_qup");
+MODULE_AUTHOR("Sagar Dharia <sdharia@codeaurora.org>");
+
+/* QUP Registers */
+enum {
+ QUP_CONFIG = 0x0,
+ QUP_STATE = 0x4,
+ QUP_IO_MODE = 0x8,
+ QUP_SW_RESET = 0xC,
+ QUP_OPERATIONAL = 0x18,
+ QUP_ERROR_FLAGS = 0x1C,
+ QUP_ERROR_FLAGS_EN = 0x20,
+ QUP_MX_READ_CNT = 0x208,
+ QUP_MX_INPUT_CNT = 0x200,
+ QUP_MX_WR_CNT = 0x100,
+ QUP_OUT_DEBUG = 0x108,
+ QUP_OUT_FIFO_CNT = 0x10C,
+ QUP_OUT_FIFO_BASE = 0x110,
+ QUP_IN_READ_CUR = 0x20C,
+ QUP_IN_DEBUG = 0x210,
+ QUP_IN_FIFO_CNT = 0x214,
+ QUP_IN_FIFO_BASE = 0x218,
+ QUP_I2C_CLK_CTL = 0x400,
+ QUP_I2C_STATUS = 0x404,
+};
+
+/* QUP States and reset values */
+enum {
+ QUP_RESET_STATE = 0,
+ QUP_RUN_STATE = 1U,
+ QUP_STATE_MASK = 3U,
+ QUP_PAUSE_STATE = 3U,
+ QUP_STATE_VALID = 1U << 2,
+ QUP_I2C_MAST_GEN = 1U << 4,
+ QUP_OPERATIONAL_RESET = 0xFF0,
+ QUP_I2C_STATUS_RESET = 0xFFFFFC,
+};
+
+/* QUP OPERATIONAL FLAGS */
+enum {
+ QUP_OUT_SVC_FLAG = 1U << 8,
+ QUP_IN_SVC_FLAG = 1U << 9,
+ QUP_MX_INPUT_DONE = 1U << 11,
+};
+
+/* I2C mini core related values */
+enum {
+ I2C_MINI_CORE = 2U << 8,
+ I2C_N_VAL = 0xF,
+};
+
+/* Packing Unpacking words in FIFOs , and IO modes*/
+enum {
+ QUP_WR_BLK_MODE = 1U << 10,
+ QUP_RD_BLK_MODE = 1U << 12,
+ QUP_UNPACK_EN = 1U << 14,
+ QUP_PACK_EN = 1U << 15,
+};
+
+/* QUP tags */
+enum {
+ QUP_OUT_NOP = 0,
+ QUP_OUT_START = 1U << 8,
+ QUP_OUT_DATA = 2U << 8,
+ QUP_OUT_STOP = 3U << 8,
+ QUP_OUT_REC = 4U << 8,
+ QUP_IN_DATA = 5U << 8,
+ QUP_IN_STOP = 6U << 8,
+ QUP_IN_NACK = 7U << 8,
+};
+
+/* Status, Error flags */
+enum {
+ I2C_STATUS_WR_BUFFER_FULL = 1U << 0,
+ I2C_STATUS_BUS_ACTIVE = 1U << 8,
+ I2C_STATUS_ERROR_MASK = 0x38000FC,
+ QUP_I2C_NACK_FLAG = 1U << 3,
+ QUP_IN_NOT_EMPTY = 1U << 5,
+ QUP_STATUS_ERROR_FLAGS = 0x7C,
+};
+
+/* GSBI Control Register */
+enum {
+ GSBI_I2C_PROTOCOL_CODE = 0x2 << 4, /* I2C protocol */
+};
+
+#define QUP_MAX_RETRIES 2000
+#define QUP_SRC_CLK_RATE 19200000 /* Default source clock rate */
+
+struct qup_i2c_dev {
+ struct device *dev;
+ void __iomem *base; /* virtual */
+ void __iomem *gsbi; /* virtual */
+ int in_irq;
+ int out_irq;
+ int err_irq;
+ int num_irqs;
+ struct clk *clk;
+ struct clk *pclk;
+ struct i2c_adapter adapter;
+
+ struct i2c_msg *msg;
+ int pos;
+ int cnt;
+ int err;
+ int mode;
+ int clk_ctl;
+ int one_bit_t;
+ int out_fifo_sz;
+ int in_fifo_sz;
+ int out_blk_sz;
+ int in_blk_sz;
+ int wr_sz;
+ struct msm_i2c_platform_data *pdata;
+ int suspended;
+ int clk_state;
+ struct timer_list pwr_timer;
+ struct mutex mlock;
+ void *complete;
+};
+
+#ifdef DEBUG
+static void
+qup_print_status(struct qup_i2c_dev *dev)
+{
+ uint32_t val;
+ val = readl(dev->base+QUP_CONFIG);
+ dev_dbg(dev->dev, "Qup config is :0x%x\n", val);
+ val = readl(dev->base+QUP_STATE);
+ dev_dbg(dev->dev, "Qup state is :0x%x\n", val);
+ val = readl(dev->base+QUP_IO_MODE);
+ dev_dbg(dev->dev, "Qup mode is :0x%x\n", val);
+}
+#else
+static inline void qup_print_status(struct qup_i2c_dev *dev)
+{
+}
+#endif
+
+static irqreturn_t
+qup_i2c_interrupt(int irq, void *devid)
+{
+ struct qup_i2c_dev *dev = devid;
+ uint32_t status = readl(dev->base + QUP_I2C_STATUS);
+ uint32_t errors = readl(dev->base + QUP_ERROR_FLAGS);
+ uint32_t op_flgs = readl(dev->base + QUP_OPERATIONAL);
+ int err = 0;
+
+ if (!dev->msg)
+ return IRQ_HANDLED;
+
+ if (status & I2C_STATUS_ERROR_MASK) {
+ dev_err(dev->dev, "QUP: I2C status flags :0x%x, irq:%d\n",
+ status, irq);
+ err = -status;
+ /* Clear Error interrupt if it's a level triggered interrupt*/
+ if (dev->num_irqs == 1)
+ writel(QUP_RESET_STATE, dev->base+QUP_STATE);
+ goto intr_done;
+ }
+
+ if (errors & QUP_STATUS_ERROR_FLAGS) {
+ dev_err(dev->dev, "QUP: QUP status flags :0x%x\n", errors);
+ err = -errors;
+ /* Clear Error interrupt if it's a level triggered interrupt*/
+ if (dev->num_irqs == 1)
+ writel(errors & QUP_STATUS_ERROR_FLAGS,
+ dev->base + QUP_ERROR_FLAGS);
+ goto intr_done;
+ }
+
+ if ((dev->num_irqs == 3) && (dev->msg->flags == I2C_M_RD)
+ && (irq == dev->out_irq))
+ return IRQ_HANDLED;
+ if (op_flgs & QUP_OUT_SVC_FLAG)
+ writel(QUP_OUT_SVC_FLAG, dev->base + QUP_OPERATIONAL);
+ if (dev->msg->flags == I2C_M_RD) {
+ if ((op_flgs & QUP_MX_INPUT_DONE) ||
+ (op_flgs & QUP_IN_SVC_FLAG))
+ writel(QUP_IN_SVC_FLAG, dev->base + QUP_OPERATIONAL);
+ else
+ return IRQ_HANDLED;
+ }
+
+intr_done:
+ dev_dbg(dev->dev, "QUP intr= %d, i2c status=0x%x, qup status = 0x%x\n",
+ irq, status, errors);
+ qup_print_status(dev);
+ dev->err = err;
+ complete(dev->complete);
+ return IRQ_HANDLED;
+}
+
+static void
+qup_i2c_pwr_mgmt(struct qup_i2c_dev *dev, unsigned int state)
+{
+ dev->clk_state = state;
+ if (state != 0) {
+ clk_enable(dev->clk);
+ if (dev->pclk)
+ clk_enable(dev->pclk);
+ } else {
+ clk_disable(dev->clk);
+ if (dev->pclk)
+ clk_disable(dev->pclk);
+ }
+}
+
+static void
+qup_i2c_pwr_timer(unsigned long data)
+{
+ struct qup_i2c_dev *dev = (struct qup_i2c_dev *) data;
+ dev_dbg(dev->dev, "QUP_Power: Inactivity based power management\n");
+ if (dev->clk_state == 1)
+ qup_i2c_pwr_mgmt(dev, 0);
+}
+
+static int
+qup_i2c_poll_writeready(struct qup_i2c_dev *dev)
+{
+ uint32_t retries = 0;
+
+ while (retries != QUP_MAX_RETRIES) {
+ uint32_t status = readl(dev->base + QUP_I2C_STATUS);
+
+ if (!(status & I2C_STATUS_WR_BUFFER_FULL)) {
+ if (!(status & I2C_STATUS_BUS_ACTIVE))
+ return 0;
+ else /* 1-bit delay before we check for bus busy */
+ udelay(dev->one_bit_t);
+ }
+ if (retries++ == 1000)
+ udelay(100);
+ }
+ qup_print_status(dev);
+ return -ETIMEDOUT;
+}
+
+static int
+qup_i2c_poll_state(struct qup_i2c_dev *dev, uint32_t state)
+{
+ uint32_t retries = 0;
+
+ dev_dbg(dev->dev, "Polling Status for state:0x%x\n", state);
+
+ while (retries != QUP_MAX_RETRIES) {
+ uint32_t status = readl(dev->base + QUP_STATE);
+
+ if ((status & (QUP_STATE_VALID | state)) ==
+ (QUP_STATE_VALID | state))
+ return 0;
+ else if (retries++ == 1000)
+ udelay(100);
+ }
+ return -ETIMEDOUT;
+}
+
+#ifdef DEBUG
+static void qup_verify_fifo(struct qup_i2c_dev *dev, uint32_t val,
+ uint32_t addr, int rdwr)
+{
+ if (rdwr)
+ dev_dbg(dev->dev, "RD:Wrote 0x%x to out_ff:0x%x\n", val, addr);
+ else
+ dev_dbg(dev->dev, "WR:Wrote 0x%x to out_ff:0x%x\n", val, addr);
+}
+#else
+static inline void qup_verify_fifo(struct qup_i2c_dev *dev, uint32_t val,
+ uint32_t addr, int rdwr)
+{
+}
+#endif
+
+static void
+qup_issue_read(struct qup_i2c_dev *dev, struct i2c_msg *msg, int *idx,
+ uint32_t carry_over)
+{
+ uint16_t addr = (msg->addr << 1) | 1;
+ /* QUP limit 256 bytes per read. By HW design, 0 in the 8-bit field
+ * is treated as 256 byte read.
+ */
+ uint16_t rd_len = ((dev->cnt == 256) ? 0 : dev->cnt);
+
+ if (*idx % 4) {
+ writel(carry_over | ((QUP_OUT_START | addr) << 16),
+ dev->base + QUP_OUT_FIFO_BASE);/* + (*idx-2)); */
+
+ qup_verify_fifo(dev, carry_over |
+ ((QUP_OUT_START | addr) << 16), (uint32_t)dev->base
+ + QUP_OUT_FIFO_BASE + (*idx - 2), 1);
+ writel((QUP_OUT_REC | rd_len),
+ dev->base + QUP_OUT_FIFO_BASE);/* + (*idx+2)); */
+
+ qup_verify_fifo(dev, (QUP_OUT_REC | rd_len),
+ (uint32_t)dev->base + QUP_OUT_FIFO_BASE + (*idx + 2), 1);
+ } else {
+ writel(((QUP_OUT_REC | rd_len) << 16) | QUP_OUT_START | addr,
+ dev->base + QUP_OUT_FIFO_BASE);/* + (*idx)); */
+
+ qup_verify_fifo(dev, QUP_OUT_REC << 16 | rd_len << 16 |
+ QUP_OUT_START | addr,
+ (uint32_t)dev->base + QUP_OUT_FIFO_BASE + (*idx), 1);
+ }
+ *idx += 4;
+}
+
+static void
+qup_issue_write(struct qup_i2c_dev *dev, struct i2c_msg *msg, int rem,
+ int *idx, uint32_t *carry_over)
+{
+ int entries = dev->cnt;
+ int empty_sl = dev->wr_sz - ((*idx) >> 1);
+ int i = 0;
+ uint32_t val = 0;
+ uint32_t last_entry = 0;
+ uint16_t addr = msg->addr << 1;
+
+ if (dev->pos == 0) {
+ if (*idx % 4) {
+ writel(*carry_over | ((QUP_OUT_START | addr) << 16),
+ dev->base + QUP_OUT_FIFO_BASE);
+
+ qup_verify_fifo(dev, *carry_over | QUP_OUT_DATA << 16 |
+ addr << 16, (uint32_t)dev->base +
+ QUP_OUT_FIFO_BASE + (*idx) - 2, 0);
+ } else
+ val = QUP_OUT_START | addr;
+ *idx += 2;
+ i++;
+ entries++;
+ } else {
+ /* Avoid setp time issue by adding 1 NOP when number of bytes
+ * are more than FIFO/BLOCK size. setup time issue can't appear
+ * otherwise since next byte to be written will always be ready
+ */
+ val = (QUP_OUT_NOP | 1);
+ *idx += 2;
+ i++;
+ entries++;
+ }
+ if (entries > empty_sl)
+ entries = empty_sl;
+
+ for (; i < (entries - 1); i++) {
+ if (*idx % 4) {
+ writel(val | ((QUP_OUT_DATA |
+ msg->buf[dev->pos]) << 16),
+ dev->base + QUP_OUT_FIFO_BASE);
+
+ qup_verify_fifo(dev, val | QUP_OUT_DATA << 16 |
+ msg->buf[dev->pos] << 16, (uint32_t)dev->base +
+ QUP_OUT_FIFO_BASE + (*idx) - 2, 0);
+ } else
+ val = QUP_OUT_DATA | msg->buf[dev->pos];
+ (*idx) += 2;
+ dev->pos++;
+ }
+ if (dev->pos < (msg->len - 1))
+ last_entry = QUP_OUT_DATA;
+ else if (rem > 1) /* not last array entry */
+ last_entry = QUP_OUT_DATA;
+ else
+ last_entry = QUP_OUT_STOP;
+ if ((*idx % 4) == 0) {
+ /*
+ * If read-start and read-command end up in different fifos, it
+ * may result in extra-byte being read due to extra-read cycle.
+ * Avoid that by inserting NOP as the last entry of fifo only
+ * if write command(s) leave 1 space in fifo.
+ */
+ if (rem > 1) {
+ struct i2c_msg *next = msg + 1;
+ if (next->addr == msg->addr && (next->flags | I2C_M_RD)
+ && *idx == ((dev->wr_sz*2) - 4)) {
+ writel(((last_entry | msg->buf[dev->pos]) |
+ ((1 | QUP_OUT_NOP) << 16)), dev->base +
+ QUP_OUT_FIFO_BASE);/* + (*idx) - 2); */
+ *idx += 2;
+ } else
+ *carry_over = (last_entry | msg->buf[dev->pos]);
+ } else {
+ writel((last_entry | msg->buf[dev->pos]),
+ dev->base + QUP_OUT_FIFO_BASE);/* + (*idx) - 2); */
+
+ qup_verify_fifo(dev, last_entry | msg->buf[dev->pos],
+ (uint32_t)dev->base + QUP_OUT_FIFO_BASE +
+ (*idx), 0);
+ }
+ } else {
+ writel(val | ((last_entry | msg->buf[dev->pos]) << 16),
+ dev->base + QUP_OUT_FIFO_BASE);/* + (*idx) - 2); */
+
+ qup_verify_fifo(dev, val | (last_entry << 16) |
+ (msg->buf[dev->pos] << 16), (uint32_t)dev->base +
+ QUP_OUT_FIFO_BASE + (*idx) - 2, 0);
+ }
+
+ *idx += 2;
+ dev->pos++;
+ dev->cnt = msg->len - dev->pos;
+}
+
+static int
+qup_update_state(struct qup_i2c_dev *dev, uint32_t state)
+{
+ if (qup_i2c_poll_state(dev, 0) != 0)
+ return -EIO;
+ writel(state, dev->base + QUP_STATE);
+ if (qup_i2c_poll_state(dev, state) != 0)
+ return -EIO;
+ return 0;
+}
+
+static int
+qup_set_read_mode(struct qup_i2c_dev *dev, int rd_len)
+{
+ uint32_t wr_mode = (dev->wr_sz < dev->out_fifo_sz) ?
+ QUP_WR_BLK_MODE : 0;
+ if (rd_len > 256) {
+ dev_err(dev->dev, "HW doesn't support READs > 256 bytes\n");
+ return -EPROTONOSUPPORT;
+ }
+ if (rd_len <= dev->in_fifo_sz) {
+ writel(wr_mode | QUP_PACK_EN | QUP_UNPACK_EN,
+ dev->base + QUP_IO_MODE);
+ writel(rd_len, dev->base + QUP_MX_READ_CNT);
+ } else {
+ writel(wr_mode | QUP_RD_BLK_MODE |
+ QUP_PACK_EN | QUP_UNPACK_EN, dev->base + QUP_IO_MODE);
+ writel(rd_len, dev->base + QUP_MX_INPUT_CNT);
+ }
+ return 0;
+}
+
+static int
+qup_set_wr_mode(struct qup_i2c_dev *dev, int rem)
+{
+ int total_len = 0;
+ int ret = 0;
+ if (dev->msg->len >= (dev->out_fifo_sz - 1)) {
+ total_len = dev->msg->len + 1 +
+ (dev->msg->len/(dev->out_blk_sz-1));
+ writel(QUP_WR_BLK_MODE | QUP_PACK_EN | QUP_UNPACK_EN,
+ dev->base + QUP_IO_MODE);
+ dev->wr_sz = dev->out_blk_sz;
+ } else
+ writel(QUP_PACK_EN | QUP_UNPACK_EN,
+ dev->base + QUP_IO_MODE);
+
+ if (rem > 1) {
+ struct i2c_msg *next = dev->msg + 1;
+ if (next->addr == dev->msg->addr &&
+ next->flags == I2C_M_RD) {
+ ret = qup_set_read_mode(dev, next->len);
+ /* make sure read start & read command are in 1 blk */
+ if ((total_len % dev->out_blk_sz) ==
+ (dev->out_blk_sz - 1))
+ total_len += 3;
+ else
+ total_len += 2;
+ }
+ }
+ /* WRITE COUNT register valid/used only in block mode */
+ if (dev->wr_sz == dev->out_blk_sz)
+ writel(total_len, dev->base + QUP_MX_WR_CNT);
+ return ret;
+}
+
+static int
+qup_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+{
+ DECLARE_COMPLETION_ONSTACK(complete);
+ struct qup_i2c_dev *dev = i2c_get_adapdata(adap);
+ int ret;
+ int rem = num;
+ long timeout;
+ int err;
+
+ del_timer_sync(&dev->pwr_timer);
+ mutex_lock(&dev->mlock);
+
+ if (dev->suspended) {
+ mutex_unlock(&dev->mlock);
+ return -EIO;
+ }
+
+ if (dev->clk_state == 0) {
+ if (dev->clk_ctl == 0) {
+ if (dev->pdata->src_clk_rate > 0)
+ clk_set_rate(dev->clk,
+ dev->pdata->src_clk_rate);
+ else
+ dev->pdata->src_clk_rate = QUP_SRC_CLK_RATE;
+ }
+ qup_i2c_pwr_mgmt(dev, 1);
+ }
+
+ /* Initialize QUP registers during first transfer */
+ if (dev->clk_ctl == 0) {
+ int fs_div;
+ int hs_div;
+ uint32_t fifo_reg;
+ writel(GSBI_I2C_PROTOCOL_CODE, dev->gsbi);
+
+ fs_div = ((dev->pdata->src_clk_rate
+ / dev->pdata->clk_freq) / 2) - 3;
+ hs_div = 3;
+ dev->clk_ctl = ((hs_div & 0x7) << 8) | (fs_div & 0xff);
+ fifo_reg = readl(dev->base + QUP_IO_MODE);
+ if (fifo_reg & 0x3)
+ dev->out_blk_sz = (fifo_reg & 0x3) * 16;
+ else
+ dev->out_blk_sz = 16;
+ if (fifo_reg & 0x60)
+ dev->in_blk_sz = ((fifo_reg & 0x60) >> 5) * 16;
+ else
+ dev->in_blk_sz = 16;
+ /*
+ * The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag'
+ * associated with each byte written/received
+ */
+ dev->out_blk_sz /= 2;
+ dev->in_blk_sz /= 2;
+ dev->out_fifo_sz = dev->out_blk_sz *
+ (2 << ((fifo_reg & 0x1C) >> 2));
+ dev->in_fifo_sz = dev->in_blk_sz *
+ (2 << ((fifo_reg & 0x380) >> 7));
+ dev_dbg(dev->dev, "QUP IN:bl:%d, ff:%d, OUT:bl:%d, ff:%d\n",
+ dev->in_blk_sz, dev->in_fifo_sz,
+ dev->out_blk_sz, dev->out_fifo_sz);
+ }
+
+ if (dev->num_irqs == 3) {
+ enable_irq(dev->in_irq);
+ enable_irq(dev->out_irq);
+ }
+ enable_irq(dev->err_irq);
+ writel(1, dev->base + QUP_SW_RESET);
+ ret = qup_i2c_poll_state(dev, QUP_RESET_STATE);
+ if (ret) {
+ dev_err(dev->dev, "QUP Busy:Trying to recover\n");
+ goto out_err;
+ }
+
+ /* Initialize QUP registers */
+ writel(0, dev->base + QUP_CONFIG);
+ writel(QUP_OPERATIONAL_RESET, dev->base + QUP_OPERATIONAL);
+ writel(QUP_STATUS_ERROR_FLAGS, dev->base + QUP_ERROR_FLAGS_EN);
+
+ writel(I2C_MINI_CORE | I2C_N_VAL, dev->base + QUP_CONFIG);
+
+ /* Initialize I2C mini core registers */
+ writel(0, dev->base + QUP_I2C_CLK_CTL);
+ writel(QUP_I2C_STATUS_RESET, dev->base + QUP_I2C_STATUS);
+
+ dev->cnt = msgs->len;
+ dev->pos = 0;
+ dev->msg = msgs;
+ while (rem) {
+ bool filled = false;
+
+ dev->wr_sz = dev->out_fifo_sz;
+ dev->err = 0;
+ dev->complete = &complete;
+
+ if (qup_i2c_poll_state(dev, QUP_I2C_MAST_GEN) != 0) {
+ ret = -EIO;
+ goto out_err;
+ }
+
+ qup_print_status(dev);
+ /* HW limits Read upto 256 bytes in 1 read without stop */
+ if (dev->msg->flags & I2C_M_RD) {
+ ret = qup_set_read_mode(dev, dev->cnt);
+ if (ret != 0)
+ goto out_err;
+ } else {
+ ret = qup_set_wr_mode(dev, rem);
+ if (ret != 0)
+ goto out_err;
+ /* Don't fill block till we get interrupt */
+ if (dev->wr_sz == dev->out_blk_sz)
+ filled = true;
+ }
+
+ err = qup_update_state(dev, QUP_RUN_STATE);
+ if (err < 0) {
+ ret = err;
+ goto out_err;
+ }
+
+ qup_print_status(dev);
+ writel(dev->clk_ctl, dev->base + QUP_I2C_CLK_CTL);
+
+ do {
+ int idx = 0;
+ uint32_t carry_over = 0;
+
+ /* Transition to PAUSE state only possible from RUN */
+ err = qup_update_state(dev, QUP_PAUSE_STATE);
+ if (err < 0) {
+ ret = err;
+ goto out_err;
+ }
+
+ qup_print_status(dev);
+ /* This operation is Write, check the next operation
+ * and decide mode
+ */
+ while (filled == false) {
+ if ((msgs->flags & I2C_M_RD) &&
+ (dev->cnt == msgs->len))
+ qup_issue_read(dev, msgs, &idx,
+ carry_over);
+ else if (!(msgs->flags & I2C_M_RD))
+ qup_issue_write(dev, msgs, rem, &idx,
+ &carry_over);
+ if (idx >= (dev->wr_sz << 1))
+ filled = true;
+ /* Start new message */
+ if (filled == false) {
+ if (msgs->flags & I2C_M_RD)
+ filled = true;
+ else if (rem > 1) {
+ /* Only combine operations with
+ * same address
+ */
+ struct i2c_msg *next = msgs + 1;
+ if (next->addr != msgs->addr ||
+ next->flags == 0)
+ filled = true;
+ else {
+ rem--;
+ msgs++;
+ dev->msg = msgs;
+ dev->pos = 0;
+ dev->cnt = msgs->len;
+ }
+ } else
+ filled = true;
+ }
+ }
+ err = qup_update_state(dev, QUP_RUN_STATE);
+ if (err < 0) {
+ ret = err;
+ goto out_err;
+ }
+ dev_dbg(dev->dev, "idx:%d, rem:%d, num:%d, mode:%d\n",
+ idx, rem, num, dev->mode);
+
+ qup_print_status(dev);
+ timeout = wait_for_completion_timeout(&complete,
+ msecs_to_jiffies(dev->out_fifo_sz));
+ if (!timeout) {
+ dev_err(dev->dev, "Transaction timed out\n");
+ writel(1, dev->base + QUP_SW_RESET);
+ ret = -ETIMEDOUT;
+ goto out_err;
+ }
+ if (dev->err) {
+ if (dev->err & QUP_I2C_NACK_FLAG)
+ dev_err(dev->dev,
+ "I2C slave addr:0x%x not connected\n",
+ dev->msg->addr);
+ else
+ dev_err(dev->dev,
+ "QUP data xfer error %d\n", dev->err);
+ ret = dev->err;
+ goto out_err;
+ }
+ if (dev->msg->flags & I2C_M_RD) {
+ int i;
+ uint32_t dval = 0;
+ for (i = 0; dev->pos < dev->msg->len; i++,
+ dev->pos++) {
+ uint32_t rd_status = readl(dev->base +
+ QUP_OPERATIONAL);
+ if (i % 2 == 0) {
+ if ((rd_status &
+ QUP_IN_NOT_EMPTY) == 0)
+ break;
+ dval = readl(dev->base +
+ QUP_IN_FIFO_BASE);
+ dev->msg->buf[dev->pos] =
+ dval & 0xFF;
+ } else
+ dev->msg->buf[dev->pos] =
+ ((dval & 0xFF0000) >>
+ 16);
+ }
+ dev->cnt -= i;
+ } else
+ filled = false; /* refill output FIFO */
+ } while (dev->cnt > 0);
+ if (dev->cnt == 0) {
+ rem--;
+ msgs++;
+ if (rem) {
+ dev->pos = 0;
+ dev->cnt = msgs->len;
+ dev->msg = msgs;
+ }
+ }
+ /* Wait for I2C bus to be idle */
+ ret = qup_i2c_poll_writeready(dev);
+ if (ret) {
+ dev_err(dev->dev,
+ "Error waiting for write ready\n");
+ goto out_err;
+ }
+ }
+
+ ret = num;
+ out_err:
+ dev->complete = NULL;
+ dev->msg = NULL;
+ dev->pos = 0;
+ dev->err = 0;
+ dev->cnt = 0;
+ disable_irq(dev->err_irq);
+ if (dev->num_irqs == 3) {
+ disable_irq(dev->in_irq);
+ disable_irq(dev->out_irq);
+ }
+ dev->pwr_timer.expires = jiffies + 3*HZ;
+ add_timer(&dev->pwr_timer);
+ mutex_unlock(&dev->mlock);
+ return ret;
+}
+
+static u32
+qup_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+}
+
+static const struct i2c_algorithm qup_i2c_algo = {
+ .master_xfer = qup_i2c_xfer,
+ .functionality = qup_i2c_func,
+};
+
+static int __devinit
+qup_i2c_probe(struct platform_device *pdev)
+{
+ struct qup_i2c_dev *dev;
+ struct resource *qup_mem, *gsbi_mem, *qup_io, *gsbi_io;
+ struct resource *in_irq, *out_irq, *err_irq;
+ struct clk *clk, *pclk;
+ int ret = 0;
+ struct msm_i2c_platform_data *pdata;
+
+ dev_dbg(&pdev->dev, "qup_i2c_probe\n");
+
+ pdata = pdev->dev.platform_data;
+ if (!pdata) {
+ dev_err(&pdev->dev, "platform data not initialized\n");
+ return -ENOSYS;
+ }
+ qup_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "qup_phys_addr");
+ if (!qup_mem) {
+ dev_err(&pdev->dev, "no qup mem resource?\n");
+ return -ENODEV;
+ }
+ gsbi_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "gsbi_qup_i2c_addr");
+ if (!gsbi_mem) {
+ dev_err(&pdev->dev, "no gsbi mem resource?\n");
+ return -ENODEV;
+ }
+
+ /*
+ * We only have 1 interrupt for new hardware targets and in_irq,
+ * out_irq will be NULL for those platforms
+ */
+ in_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
+ "qup_in_intr");
+
+ out_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
+ "qup_out_intr");
+
+ err_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
+ "qup_err_intr");
+ if (!err_irq) {
+ dev_err(&pdev->dev, "no error irq resource?\n");
+ return -ENODEV;
+ }
+
+ qup_io = request_mem_region(qup_mem->start, resource_size(qup_mem),
+ pdev->name);
+ if (!qup_io) {
+ dev_err(&pdev->dev, "QUP region already claimed\n");
+ return -EBUSY;
+ }
+ gsbi_io = request_mem_region(gsbi_mem->start, resource_size(gsbi_mem),
+ pdev->name);
+ if (!gsbi_io) {
+ release_mem_region(qup_mem->start, resource_size(qup_mem));
+ dev_err(&pdev->dev, "GSBI region already claimed\n");
+ return -EBUSY;
+ }
+
+ clk = clk_get(&pdev->dev, "qup_clk");
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "Could not get clock\n");
+ ret = PTR_ERR(clk);
+ goto err_clk_get_failed;
+ }
+
+ pclk = clk_get(&pdev->dev, "qup_pclk");
+ if (IS_ERR(pclk))
+ pclk = NULL;
+
+ if (!pdata->msm_i2c_config_gpio) {
+ dev_err(&pdev->dev, "config_gpio function not initialized\n");
+ ret = -ENOSYS;
+ goto err_config_failed;
+ }
+
+ /* We support frequencies upto FAST Mode(400KHz) */
+ if (pdata->clk_freq <= 0 ||
+ pdata->clk_freq > 400000) {
+ dev_err(&pdev->dev, "clock frequency not supported\n");
+ ret = -EIO;
+ goto err_config_failed;
+ }
+
+ dev = kzalloc(sizeof(struct qup_i2c_dev), GFP_KERNEL);
+ if (!dev) {
+ ret = -ENOMEM;
+ goto err_alloc_dev_failed;
+ }
+
+ dev->dev = &pdev->dev;
+ if (in_irq)
+ dev->in_irq = in_irq->start;
+ if (out_irq)
+ dev->out_irq = out_irq->start;
+ dev->err_irq = err_irq->start;
+ if (in_irq && out_irq)
+ dev->num_irqs = 3;
+ else
+ dev->num_irqs = 1;
+ dev->clk = clk;
+ dev->pclk = pclk;
+ dev->base = ioremap(qup_mem->start, resource_size(qup_mem));
+ if (!dev->base) {
+ ret = -ENOMEM;
+ goto err_ioremap_failed;
+ }
+
+ /* Configure GSBI block to use I2C functionality */
+ dev->gsbi = ioremap(gsbi_mem->start, resource_size(gsbi_mem));
+ if (!dev->gsbi) {
+ ret = -ENOMEM;
+ goto err_gsbi_failed;
+ }
+
+ platform_set_drvdata(pdev, dev);
+
+ dev->one_bit_t = USEC_PER_SEC/pdata->clk_freq;
+ dev->pdata = pdata;
+ dev->clk_ctl = 0;
+
+ /*
+ * We use num_irqs to also indicate if we got 3 interrupts or just 1.
+ * If we have just 1, we use err_irq as the general purpose irq
+ * and handle the changes in ISR accordingly
+ * Per Hardware guidelines, if we have 3 interrupts, they are always
+ * edge triggering, and if we have 1, it's always level-triggering
+ */
+ if (dev->num_irqs == 3) {
+ ret = request_irq(dev->in_irq, qup_i2c_interrupt,
+ IRQF_TRIGGER_RISING, "qup_in_intr", dev);
+ if (ret) {
+ dev_err(&pdev->dev, "request_in_irq failed\n");
+ goto err_request_irq_failed;
+ }
+ /*
+ * We assume out_irq exists if in_irq does since platform
+ * configuration either has 3 interrupts assigned to QUP or 1
+ */
+ ret = request_irq(dev->out_irq, qup_i2c_interrupt,
+ IRQF_TRIGGER_RISING, "qup_out_intr", dev);
+ if (ret) {
+ dev_err(&pdev->dev, "request_out_irq failed\n");
+ free_irq(dev->in_irq, dev);
+ goto err_request_irq_failed;
+ }
+ ret = request_irq(dev->err_irq, qup_i2c_interrupt,
+ IRQF_TRIGGER_RISING, "qup_err_intr", dev);
+ if (ret) {
+ dev_err(&pdev->dev, "request_err_irq failed\n");
+ free_irq(dev->out_irq, dev);
+ free_irq(dev->in_irq, dev);
+ goto err_request_irq_failed;
+ }
+ } else {
+ ret = request_irq(dev->err_irq, qup_i2c_interrupt,
+ IRQF_TRIGGER_HIGH, "qup_err_intr", dev);
+ if (ret) {
+ dev_err(&pdev->dev, "request_err_irq failed\n");
+ goto err_request_irq_failed;
+ }
+ }
+ disable_irq(dev->err_irq);
+ if (dev->num_irqs == 3) {
+ disable_irq(dev->in_irq);
+ disable_irq(dev->out_irq);
+ }
+ i2c_set_adapdata(&dev->adapter, dev);
+ dev->adapter.algo = &qup_i2c_algo;
+ strlcpy(dev->adapter.name,
+ "QUP I2C adapter",
+ sizeof(dev->adapter.name));
+ dev->adapter.nr = pdev->id;
+ pdata->msm_i2c_config_gpio(dev->adapter.nr, 1);
+
+ dev->suspended = 0;
+ mutex_init(&dev->mlock);
+ dev->clk_state = 0;
+ setup_timer(&dev->pwr_timer, qup_i2c_pwr_timer, (unsigned long) dev);
+
+ ret = i2c_add_numbered_adapter(&dev->adapter);
+ if (ret) {
+ dev_err(&pdev->dev, "i2c_add_adapter failed\n");
+ if (dev->num_irqs == 3) {
+ free_irq(dev->out_irq, dev);
+ free_irq(dev->in_irq, dev);
+ }
+ free_irq(dev->err_irq, dev);
+ } else
+ return 0;
+
+err_request_irq_failed:
+ iounmap(dev->gsbi);
+err_gsbi_failed:
+ iounmap(dev->base);
+err_ioremap_failed:
+ kfree(dev);
+err_alloc_dev_failed:
+err_config_failed:
+ clk_put(clk);
+ if (pclk)
+ clk_put(pclk);
+err_clk_get_failed:
+ release_mem_region(gsbi_mem->start, resource_size(gsbi_mem));
+ release_mem_region(qup_mem->start, resource_size(qup_mem));
+ return ret;
+}
+
+static int __devexit
+qup_i2c_remove(struct platform_device *pdev)
+{
+ struct qup_i2c_dev *dev = platform_get_drvdata(pdev);
+ struct resource *qup_mem, *gsbi_mem;
+
+ /* Grab mutex to ensure ongoing transaction is over */
+ mutex_lock(&dev->mlock);
+ dev->suspended = 1;
+ mutex_unlock(&dev->mlock);
+ mutex_destroy(&dev->mlock);
+ del_timer_sync(&dev->pwr_timer);
+ if (dev->clk_state != 0)
+ qup_i2c_pwr_mgmt(dev, 0);
+ platform_set_drvdata(pdev, NULL);
+ if (dev->num_irqs == 3) {
+ free_irq(dev->out_irq, dev);
+ free_irq(dev->in_irq, dev);
+ }
+ free_irq(dev->err_irq, dev);
+ i2c_del_adapter(&dev->adapter);
+ clk_put(dev->clk);
+ if (dev->pclk)
+ clk_put(dev->pclk);
+ iounmap(dev->gsbi);
+ iounmap(dev->base);
+ kfree(dev);
+ gsbi_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "gsbi_qup_i2c_addr");
+ release_mem_region(gsbi_mem->start, resource_size(gsbi_mem));
+ qup_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "qup_phys_addr");
+ release_mem_region(qup_mem->start, resource_size(qup_mem));
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int qup_i2c_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct qup_i2c_dev *qup = platform_get_drvdata(pdev);
+
+ /* Grab mutex to ensure ongoing transaction is over */
+ mutex_lock(&qup->mlock);
+ qup->suspended = 1;
+ mutex_unlock(&qup->mlock);
+ del_timer_sync(&qup->pwr_timer);
+ if (qup->clk_state != 0)
+ qup_i2c_pwr_mgmt(qup, 0);
+ return 0;
+}
+
+static int qup_i2c_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct qup_i2c_dev *qup = platform_get_drvdata(pdev);
+
+ qup->suspended = 0;
+ return 0;
+}
+
+static const SIMPLE_DEV_PM_OPS(qup_i2c_pm_ops,
+ qup_i2c_suspend, qup_i2c_resume);
+#endif /* CONFIG_PM */
+
+static struct platform_driver qup_i2c_driver = {
+ .probe = qup_i2c_probe,
+ .remove = __devexit_p(qup_i2c_remove),
+ .driver = {
+ .name = "qup_i2c",
+ .owner = THIS_MODULE,
+#ifdef CONFIG_PM
+ .pm = &qup_i2c_pm_ops,
+#endif
+ },
+};
+
+/* QUP may be needed to bring up other drivers */
+static int __init
+qup_i2c_init_driver(void)
+{
+ return platform_driver_register(&qup_i2c_driver);
+}
+arch_initcall(qup_i2c_init_driver);
+
+static void __exit qup_i2c_exit_driver(void)
+{
+ platform_driver_unregister(&qup_i2c_driver);
+}
+module_exit(qup_i2c_exit_driver);
diff --git a/include/linux/i2c-msm.h b/include/linux/i2c-msm.h
new file mode 100644
index 0000000..a09dea7
--- /dev/null
+++ b/include/linux/i2c-msm.h
@@ -0,0 +1,29 @@
+/*
+ * Qualcomm MSM i2c Controller Platform Data
+ *
+ * Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+#ifndef __LINUX_I2C_MSM_H
+#define __LINUX_I2C_MSM_H
+
+struct msm_i2c_platform_data {
+ int clk_freq;
+ int src_clk_rate;
+ int (*msm_i2c_config_gpio)(int iface, int config_type);
+};
+
+#endif /* __LINUX_I2C_MSM_H */
--
1.7.1.1

Sent by an employee of the Qualcomm Innovation Center, Inc.