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* [PATCH 0/5] PXA LX platform support
@ 2009-04-18 14:19 Russell King - ARM Linux
       [not found] ` <20090418141932.GA1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
  0 siblings, 1 reply; 9+ messages in thread
From: Russell King - ARM Linux @ 2009-04-18 14:19 UTC (permalink / raw)
  To: linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW
  Cc: Ben Dooks, linux-i2c-u79uwXL29TY76Z2rM5mHXA, Eric Miao,
	Dmitry Torokhov, linux-input-u79uwXL29TY76Z2rM5mHXA,
	linux-pcmcia-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r

The following series adds basic support for the LX platform.  This
platform is a portable small netbook style machine, with support
for touch screen LCD, sound, MMC/SD, one serial port, CF, PCMCIA
and MMC.

The entire series is posted to the linux-arm-kernel list; individual
patches are only copied to relevent people/lists.

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
       [not found] ` <20090418141932.GA1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
@ 2009-04-18 14:20   ` Russell King
       [not found]     ` <1240064452-14691-1-git-send-email-linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
  0 siblings, 1 reply; 9+ messages in thread
From: Russell King @ 2009-04-18 14:20 UTC (permalink / raw)
  To: linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW
  Cc: Ben Dooks, linux-i2c-u79uwXL29TY76Z2rM5mHXA

The PCON device on the LX platform is the heart of the platform,
managing the power, providing battery information, booting, suspend/
resume and keyboard services to the PXA CPU.

Communication between the PXA and PCON is via a multi-master I2C bus,
where both the PCON and PXA behave like an 256 byte EEPROM, and each
reads and writes locations within that namespace.

It has a nasty habbit of resetting the PXA CPU if it sees something
it doesn't like, so we have to be careful how we communicate with the
PCON.  This happens (eg) if we hold the I2C bus for any "unreasonable"
length of time, or ignore the PCON's attempt to address us as a slave.

Signed-off-by: Russell King <rmk+kernel-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
CC: Ben Dooks <ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org>
CC: <linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
---
 arch/arm/mach-pxa/include/mach/lx-pcon.h |  117 ++++++++
 drivers/i2c/chips/Kconfig                |   10 +
 drivers/i2c/chips/Makefile               |    1 +
 drivers/i2c/chips/lx-pcon.c              |  428 ++++++++++++++++++++++++++++++
 4 files changed, 556 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/mach-pxa/include/mach/lx-pcon.h
 create mode 100644 drivers/i2c/chips/lx-pcon.c

diff --git a/arch/arm/mach-pxa/include/mach/lx-pcon.h b/arch/arm/mach-pxa/include/mach/lx-pcon.h
new file mode 100644
index 0000000..acc410d
--- /dev/null
+++ b/arch/arm/mach-pxa/include/mach/lx-pcon.h
@@ -0,0 +1,117 @@
+/*
+ * PCON addresses
+ */
+#define PCON_KEYBOARD_CMD_ADDR		(0x00)
+#define PCON_KEYBOARD_CMD_VAL_READY	(0)
+#define PCON_KEYBOARD_CMD_VAL_BUSY 	(1)
+#define PCON_POWER_CF_ADDR		(0x02)
+#define PCON_POWER_PCMCIA_ADDR		(0x03)
+#define PCON_POWER_CFG_ADDR		(0x04)
+#define PCON_PWRSTATE_ADDR		(0x05)
+#define PCON_CMD_ADDR			(0x0c)	/* 1 + 8 args */
+
+typedef enum pcon_pwrstate_e {
+	PCON_PWRSTATE_HWReset    = 0,
+	PCON_PWRSTATE_SWReset    = 1,
+	PCON_PWRSTATE_Off        = 2,
+	PCON_PWRSTATE_Suspend    = 3,
+	PCON_PWRSTATE_Sleep      = 4,
+	PCON_PWRSTATE_Booting    = 5,
+	PCON_PWRSTATE_LoadingOS  = 6,
+	PCON_PWRSTATE_Idle       = 7,
+	PCON_PWRSTATE_Run        = 8,
+	PCON_PWRSTATE_Comatose   = 9,
+	PCON_PWRSTATE_PowerFail  = 10
+} pcon_pwrstate_t;
+
+extern void lx_pwr_setstate(pcon_pwrstate_t);
+extern void pcon_pwr_setstate(pcon_pwrstate_t);
+
+typedef enum {
+	PCON_CMD_Ready          = 0,
+	PCON_CMD_ADCRead        = 9,
+	PCON_CMD_GetVersion     = 10,
+	PCON_CMD_SetMMCPower    = 11,
+	PCON_CMD_SetModemPower  = 12,
+	PCON_CMD_SetUSBPower    = 13,
+	PCON_CMD_SetRedLED      = 14,
+	PCON_CMD_SetSerialPower = 15,
+	PCON_CMD_GetSerialCfg   = 17,
+	PCON_CMD_BatteryMonitor = 18,
+	PCON_CMD_GetMMCPower    = 19,
+	PCON_CMD_GetVModemPower = 20,
+	PCON_CMD_GetUSBPower    = 21,
+	PCON_CMD_SetWakeupAlarm = 22,
+} pcon_cmd_t;
+
+/*
+ * Host EEPROM emulation addresses
+ */
+#define PHST_KEYBOARD_START		(0x00)
+#define PHST_KEYBOARD_SIZE		(1)
+#define PHST_SERIAL_START		(0x02)
+#define PHST_SERIAL_SIZE		(1)
+#define PHST_POWER_START		(0x05)
+#define PHST_POWER_SIZE			(1)
+#define PHST_CMDRESP_START		(0x0d)
+#define PHST_CMDRESP_SIZE		(8)
+
+struct lx_i2cslave_watcher {
+	u16 start;
+	u16 size;
+	void (*write)(void *, unsigned int addr, unsigned char newval);
+};
+
+struct lx_i2cslave_watch {
+	struct list_head node;
+	u16 start;
+	u16 end;
+	struct lx_i2cslave_watcher *ops;
+	void *data;
+};
+
+#define I2C_EEPROM_EMU_SIZE (256)
+
+struct lx_eeprom_emu {
+	u16 size;
+	u16 ptr;
+	unsigned int seen_start;
+	struct list_head watch;
+
+	unsigned char bytes[I2C_EEPROM_EMU_SIZE];
+};
+
+extern int lx_i2cslave_addwatcher(struct lx_i2cslave_watcher *, void *data);
+extern void lx_i2cslave_delwatcher(struct lx_i2cslave_watcher *, void *data);
+
+
+
+#define PCON_FLG_ASYNC          (1)
+
+/* exported functions */
+
+extern int pcon_simple_cmd(unsigned int, unsigned int, unsigned int);
+#define pcon_set_usbhost_power(on)	\
+	pcon_simple_cmd(PCON_CMD_SetUSBPower, !!(on), PCON_FLG_ASYNC)
+#define pcon_set_mmc_power(on)		\
+	pcon_simple_cmd(PCON_CMD_SetMMCPower, !!(on), 0)
+#define pcon_set_modem_power(on)	\
+	pcon_simple_cmd(PCON_CMD_SetModemPower, !!(on), 0)
+#define pcon_set_serial_power(on)	\
+	pcon_simple_cmd(PCON_CMD_SetSerialPower, !!(on), PCON_FLG_ASYNC)
+
+#define pcon_monitorbattery(on, flag)	\
+	pcon_simple_cmd(PCON_CMD_BatteryMonitor, !!(on), flag)
+#define pcon_setredled(on)		\
+	pcon_simple_cmd(PCON_CMD_SetRedLED, !!(on), 0)
+
+extern int pcon_simple_write(unsigned int, unsigned int, unsigned int);
+#define pcon_kbd_ack()			\
+	pcon_simple_write(PCON_KEYBOARD_CMD_ADDR, PCON_KEYBOARD_CMD_VAL_READY, PCON_FLG_ASYNC)
+#define pcon_set_pcmcia_power(on)	\
+	pcon_simple_write(PCON_POWER_PCMCIA_ADDR, !!(on), 0)
+#define pcon_set_cf_power(on)		\
+	pcon_simple_write(PCON_POWER_CF_ADDR, !!(on), 0)
+
+struct rtc_time;
+extern int pcon_rtc_wakeup(struct rtc_time *tm);
diff --git a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig
index 8f8c81e..501fb5d 100644
--- a/drivers/i2c/chips/Kconfig
+++ b/drivers/i2c/chips/Kconfig
@@ -89,4 +89,14 @@ config SENSORS_TSL2550
 	  This driver can also be built as a module.  If so, the module
 	  will be called tsl2550.
 
+config LX_PCON
+	bool
+	depends on I2C=y && MACH_NETBOOKPRO
+	default y
+	help
+	  The LX PCON driver is required to communicate with the LX
+	  platform power control device.  This device is the heart
+	  of the system, providing power management and keyboard
+	  handling for the system.
+
 endmenu
diff --git a/drivers/i2c/chips/Makefile b/drivers/i2c/chips/Makefile
index 55a3760..871c8ae 100644
--- a/drivers/i2c/chips/Makefile
+++ b/drivers/i2c/chips/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_SENSORS_MAX6875)	+= max6875.o
 obj-$(CONFIG_SENSORS_PCA9539)	+= pca9539.o
 obj-$(CONFIG_SENSORS_PCF8574)	+= pcf8574.o
 obj-$(CONFIG_PCF8575)		+= pcf8575.o
+obj-$(CONFIG_LX_PCON)		+= lx-pcon.o
 obj-$(CONFIG_SENSORS_TSL2550)	+= tsl2550.o
 
 ifeq ($(CONFIG_I2C_DEBUG_CHIP),y)
diff --git a/drivers/i2c/chips/lx-pcon.c b/drivers/i2c/chips/lx-pcon.c
new file mode 100644
index 0000000..67a0a5b
--- /dev/null
+++ b/drivers/i2c/chips/lx-pcon.c
@@ -0,0 +1,428 @@
+/*
+ *  linux/drivers/i2c/chips/lx-pcon.c
+ *
+ *  Driver for LX PCON chip
+ *  Copyright (C) 2004 Simtec Electronics
+ *
+ *  based on linux/drivers/acorn/char/pcf8583.c
+ *  Copyright (C) 2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+/* This driver provides the low-level i2c sending for the LX's
+ * power-management and general support processor. This allows other parts
+ * of the system to send messages to the chip for processing (including
+ * the userland)
+ *
+ * Note, this code does not provide the i2c client facilities needed by
+ * the PCon to send data to the systems that need information feeding in.
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/ioctl.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/kthread.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+
+#include <mach/lx-pcon.h>
+
+struct pcon_client {
+	struct i2c_client	*client;
+	struct task_struct	*thread;
+	wait_queue_head_t	thr_wait;
+	struct platform_device	*kbd;
+	struct platform_device	*pwr;
+	void                   *pcon_dev;
+};
+
+/* pcon_cmd_ent
+ *
+ * command entry for the command queue
+*/
+
+struct pcon_cmd_ent {
+	struct pcon_cmd_ent	*next;
+	struct completion	done;
+
+	unsigned int		flags;
+
+#define PCON_FLG__ASYNC		(1 << 0)	/* defined elsewhere */
+#define PCON_FLG_CHKRDY		(1 << 1)
+#define PCON_FLG_RECVMSG	(1 << 2)
+
+	int			sendlen;
+	int			result;
+	unsigned char		sendmsg[16];
+	unsigned char		recvmsg[1];
+};
+
+static struct pcon_cmd_ent *queue;
+static struct pcon_client *cur_client;
+
+#define PCON_I2C_ADDR (0x26 >> 1)
+
+static int
+pcon_do_read(struct pcon_client *pc, int loc, unsigned char *result)
+{
+	struct i2c_client *client = pc->client;
+	unsigned char loc_data[1];
+	struct i2c_msg msgs[2] = {
+		{
+			.addr	= client->addr,
+			.flags	= 0,
+			.len	= 1,
+			.buf	= loc_data,
+		}, {
+			.addr	= client->addr,
+			.flags	= I2C_M_RD,
+			.len	= 1,
+			.buf	= result,
+		}
+	};
+
+	loc_data[0] = loc;
+
+	return i2c_transfer(client->adapter, msgs, 2);
+}
+
+static int pcon_send(struct pcon_client *pc, unsigned char *data, int length)
+{
+	struct i2c_client *client = pc->client;
+	struct i2c_msg msgs[1] = {
+		{
+			.addr	= client->addr,
+			.flags	= 0,
+			.len	= length,
+			.buf	= data
+		}
+	};
+
+	return i2c_transfer(client->adapter, msgs, 1) == 1 ? 1 : 0;
+}
+
+static int pcon_check_ready(struct pcon_client *client)
+{
+	unsigned char inbuff;
+	int ret;
+
+	while (1) {
+		/* the sfi code places this in the way to make sure that the
+		 * friendly pcon isn't going to ack us... dunno if this is
+		 * going to help us or not with our problems with reboot
+		 * after suspend...
+		 *
+		 * yep, this delay fixes the problem.
+		 */
+		msleep(100);
+
+		ret = pcon_do_read(client, PCON_CMD_ADDR, &inbuff);
+
+		if (ret == 2 && inbuff == PCON_CMD_Ready)
+			return 0;
+
+		/* ok, we didn't get an ok response, let us
+		 * wait for a little while and try again
+		 */
+		msleep(100);
+	}
+
+	return 0;
+}
+
+static int pcon_thread(void *param)
+{
+	struct pcon_client *pc = param;
+	unsigned long flags;
+	int ret;
+
+	current->flags |= PF_NOFREEZE;
+
+	while (1) {
+		struct pcon_cmd_ent *cmd;
+
+		wait_event_interruptible(pc->thr_wait, queue ||
+					 kthread_should_stop());
+
+		if (kthread_should_stop())
+			break;
+
+		/*
+		 * remove one item from the queue, and execute it
+		 */
+		local_irq_save(flags);
+		cmd = queue;
+		if (cmd != NULL)
+			queue = cmd->next;
+		local_irq_restore(flags);
+
+		if (!cmd)
+			continue;
+
+		if (cmd->flags & PCON_FLG_CHKRDY)
+			pcon_check_ready(pc);
+
+		if (cmd->flags & PCON_FLG_RECVMSG)
+			ret = pcon_do_read(pc, cmd->sendmsg[0], cmd->recvmsg);
+		else
+			ret = pcon_send(pc, cmd->sendmsg, cmd->sendlen);
+
+		cmd->result = ret;
+
+		if ((cmd->flags & PCON_FLG_ASYNC) == 0) {
+			complete(&cmd->done);
+		} else {
+			kfree(cmd);
+		}
+	}
+
+	return 0;
+}
+
+static int pcon_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+	struct pcon_client *pc;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	dev_info(&client->dev, "LX: pcon found at 0x%02x\n", client->addr);
+
+	pc = kzalloc(sizeof(*pc), GFP_KERNEL);
+	if (pc == NULL) {
+		pr_err("pcon: no memory for pcon client data\n");
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	pc->client = client;
+	i2c_set_clientdata(client, pc);
+
+	pc->kbd = platform_device_alloc("lx-kbd", -1);
+	pc->pwr = platform_device_alloc("lx-pwr", -1);
+	if (!pc->kbd || !pc->pwr) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	pc->kbd->dev.parent = &client->dev;
+	pc->pwr->dev.parent = &client->dev;
+
+	init_waitqueue_head(&pc->thr_wait);
+
+	cur_client = pc;
+
+	pc->thread = kthread_run(pcon_thread, pc, "pcon");
+	if (IS_ERR(pc->thread)) {
+		ret = PTR_ERR(pc->thread);
+		pr_err("pcon: cannot start thread: %d\n", ret);
+		goto done;
+	}
+
+	ret = platform_device_add(pc->kbd);
+	if (ret < 0)
+		goto done;
+
+	ret = platform_device_add(pc->pwr);
+	if (ret < 0) {
+		platform_device_del(pc->kbd);
+		goto done;
+	}
+
+	if (1) {
+		pr_info("Moving power state to Run\n");
+		pcon_pwr_setstate(PCON_PWRSTATE_Run);
+	}
+	ret = 0;
+
+done:
+	if (ret < 0) {
+		if (!IS_ERR(pc->thread) && pc->thread)
+			kthread_stop(pc->thread);
+		platform_device_put(pc->kbd);
+		platform_device_put(pc->pwr);
+		kfree(pc);
+	}
+
+	return ret;
+}
+
+static int pcon_remove(struct i2c_client *client)
+{
+	struct pcon_client *pc = i2c_get_clientdata(client);
+
+	platform_device_unregister(pc->pwr);
+	platform_device_unregister(pc->kbd);
+	kthread_stop(pc->thread);
+	kfree(pc);
+	return 0;
+}
+
+static int
+__pcon_command(struct pcon_client *pc, unsigned int flags, unsigned char *msg,
+		int len, int *result)
+{
+	struct pcon_cmd_ent *ent;
+	unsigned long irq_flags;
+	int ret = 0;
+
+	ent = kmalloc(sizeof(*ent), (flags & PCON_FLG_ASYNC)
+		? GFP_ATOMIC : GFP_KERNEL);
+	if (ent == NULL) {
+		pr_err("%s: no memory for command\n", __func__);
+		return -ENOMEM;
+	}
+
+	init_completion(&ent->done);
+	ent->next    = NULL;
+	ent->flags   = flags;
+	ent->sendlen = len;
+	memcpy(ent->sendmsg, msg, len);
+
+	local_irq_save(irq_flags);
+
+	if (queue == NULL) {
+		queue = ent;
+	} else {
+		struct pcon_cmd_ent *ptr = queue;
+
+		for (; ptr->next != NULL; ptr = ptr->next)
+			;
+
+		ptr->next = ent;
+	}
+
+	local_irq_restore(irq_flags);
+
+	if (pc != NULL)
+		wake_up(&pc->thr_wait);
+
+	if (flags & PCON_FLG_ASYNC) {
+		/* nothing to do, leave it to it. */
+	} else {
+		WARN_ON(pc == NULL);
+		wait_for_completion(&ent->done);
+
+		if (flags & PCON_FLG_RECVMSG) {
+			if (ent->result == 2) {
+				if (result)
+					*result = ent->recvmsg ? 1 : 0;
+				ret = 0;
+			} else
+				ret = ent->result;
+		}
+
+		/* dump this, we've been left with it*/
+		kfree(ent);
+	}
+
+	return ret;
+}
+
+int pcon_simple_cmd(unsigned int cmd, unsigned int val, unsigned int flags)
+{
+	unsigned char sendmsg[3];
+
+	might_sleep_if(flags != PCON_FLG_ASYNC);
+
+	sendmsg[0] = PCON_CMD_ADDR;
+	sendmsg[1] = cmd;
+	sendmsg[2] = val;
+
+	return __pcon_command(cur_client, flags | PCON_FLG_CHKRDY,
+			      sendmsg, sizeof(sendmsg), NULL);
+}
+EXPORT_SYMBOL(pcon_simple_cmd);
+
+int pcon_simple_write(unsigned int addr, unsigned int val, unsigned int flags)
+{
+	unsigned char sendmsg[2];
+
+	might_sleep_if(flags != PCON_FLG_ASYNC);
+
+	sendmsg[0] = addr;
+	sendmsg[1] = val;
+
+	return __pcon_command(cur_client, flags, sendmsg, sizeof(sendmsg),
+			      NULL);
+}
+EXPORT_SYMBOL(pcon_simple_write);
+
+int pcon_rtc_wakeup(struct rtc_time *tm)
+{
+	unsigned char sendmsg[10];
+
+	might_sleep();
+
+	sendmsg[0] = PCON_CMD_ADDR;
+	sendmsg[1] = PCON_CMD_SetWakeupAlarm;
+	sendmsg[2] = tm->tm_sec;
+	sendmsg[3] = tm->tm_min;
+	sendmsg[4] = tm->tm_hour;
+	sendmsg[5] = tm->tm_wday; /* 6 = Saturday */
+	sendmsg[6] = tm->tm_mday; /* 1 = 1st */
+	sendmsg[7] = tm->tm_mon;
+	sendmsg[8] = tm->tm_year >> 8;
+	sendmsg[9] = tm->tm_year & 255;
+
+	return __pcon_command(cur_client, PCON_FLG_CHKRDY, sendmsg,
+			      sizeof(sendmsg), NULL);
+}
+EXPORT_SYMBOL(pcon_rtc_wakeup);
+
+void pcon_pwr_setstate(pcon_pwrstate_t pwrstate)
+{
+	unsigned char sendmsg[2];
+
+	if (cur_client == NULL) {
+		pr_err("%s: no client for write\n", __func__);
+		return;
+	}
+
+	sendmsg[0] = PCON_PWRSTATE_ADDR;
+	sendmsg[1] = pwrstate;
+
+	pcon_send(cur_client, sendmsg, sizeof(sendmsg));
+}
+
+
+static const struct i2c_device_id pcon_id[] = {
+	{ "lxpcon", 0 },
+	{ }
+};
+
+static struct i2c_driver pcon_driver = {
+	.driver		= {
+		.owner		= THIS_MODULE,
+		.name		= "pcon",
+	},
+	.id_table	= pcon_id,
+	.probe		= pcon_probe,
+	.remove		= pcon_remove,
+};
+
+static __init int pcon_init(void)
+{
+	return i2c_add_driver(&pcon_driver);
+}
+
+static __exit void pcon_exit(void)
+{
+	i2c_del_driver(&pcon_driver);
+}
+
+MODULE_AUTHOR("Ben Dooks <ben-Y5A6D6n0/KfQXOPxS62xeg@public.gmane.org>");
+MODULE_DESCRIPTION("Psion Teklogix NetBookPro PCon chip driver");
+
+module_init(pcon_init);
+module_exit(pcon_exit);
-- 
1.6.0.6

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
       [not found]     ` <1240064452-14691-1-git-send-email-linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
@ 2009-04-18 14:29       ` Jean Delvare
       [not found]         ` <20090418162900.0dc16531-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
  0 siblings, 1 reply; 9+ messages in thread
From: Jean Delvare @ 2009-04-18 14:29 UTC (permalink / raw)
  To: Russell King
  Cc: linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW, Ben Dooks,
	linux-i2c-u79uwXL29TY76Z2rM5mHXA

On Sat, 18 Apr 2009 15:20:48 +0100, Russell King wrote:
> The PCON device on the LX platform is the heart of the platform,
> managing the power, providing battery information, booting, suspend/
> resume and keyboard services to the PXA CPU.
> 
> Communication between the PXA and PCON is via a multi-master I2C bus,
> where both the PCON and PXA behave like an 256 byte EEPROM, and each
> reads and writes locations within that namespace.
> 
> It has a nasty habbit of resetting the PXA CPU if it sees something
> it doesn't like, so we have to be careful how we communicate with the
> PCON.  This happens (eg) if we hold the I2C bus for any "unreasonable"
> length of time, or ignore the PCON's attempt to address us as a slave.
> 
> Signed-off-by: Russell King <rmk+kernel-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
> CC: Ben Dooks <ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org>
> CC: <linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
> ---
>  arch/arm/mach-pxa/include/mach/lx-pcon.h |  117 ++++++++
>  drivers/i2c/chips/Kconfig                |   10 +
>  drivers/i2c/chips/Makefile               |    1 +

Nack. Really, people, please read the files you modify, it isn't that
hard.

-- 
Jean Delvare

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
       [not found]         ` <20090418162900.0dc16531-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
@ 2009-04-18 14:42           ` Russell King - ARM Linux
       [not found]             ` <20090418144234.GB1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
  0 siblings, 1 reply; 9+ messages in thread
From: Russell King - ARM Linux @ 2009-04-18 14:42 UTC (permalink / raw)
  To: Jean Delvare
  Cc: linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW, Ben Dooks,
	linux-i2c-u79uwXL29TY76Z2rM5mHXA

On Sat, Apr 18, 2009 at 04:29:00PM +0200, Jean Delvare wrote:
> On Sat, 18 Apr 2009 15:20:48 +0100, Russell King wrote:
> > The PCON device on the LX platform is the heart of the platform,
> > managing the power, providing battery information, booting, suspend/
> > resume and keyboard services to the PXA CPU.
> > 
> > Communication between the PXA and PCON is via a multi-master I2C bus,
> > where both the PCON and PXA behave like an 256 byte EEPROM, and each
> > reads and writes locations within that namespace.
> > 
> > It has a nasty habbit of resetting the PXA CPU if it sees something
> > it doesn't like, so we have to be careful how we communicate with the
> > PCON.  This happens (eg) if we hold the I2C bus for any "unreasonable"
> > length of time, or ignore the PCON's attempt to address us as a slave.
> > 
> > Signed-off-by: Russell King <rmk+kernel-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
> > CC: Ben Dooks <ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org>
> > CC: <linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
> > ---
> >  arch/arm/mach-pxa/include/mach/lx-pcon.h |  117 ++++++++
> >  drivers/i2c/chips/Kconfig                |   10 +
> >  drivers/i2c/chips/Makefile               |    1 +
> 
> Nack. Really, people, please read the files you modify, it isn't that
> hard.

Maybe you can suggest a better place for it?

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
       [not found]             ` <20090418144234.GB1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
@ 2009-04-18 17:34               ` Mark Brown
  2009-04-18 18:10                 ` Russell King - ARM Linux
  0 siblings, 1 reply; 9+ messages in thread
From: Mark Brown @ 2009-04-18 17:34 UTC (permalink / raw)
  To: Russell King - ARM Linux
  Cc: Jean Delvare, linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW,
	Ben Dooks, linux-i2c-u79uwXL29TY76Z2rM5mHXA

On Sat, Apr 18, 2009 at 03:42:34PM +0100, Russell King - ARM Linux wrote:
> On Sat, Apr 18, 2009 at 04:29:00PM +0200, Jean Delvare wrote:

> > > The PCON device on the LX platform is the heart of the platform,
> > > managing the power, providing battery information, booting, suspend/
> > > resume and keyboard services to the PXA CPU.

> > Nack. Really, people, please read the files you modify, it isn't that
> > hard.

> Maybe you can suggest a better place for it?

drivers/mfd?

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
  2009-04-18 17:34               ` Mark Brown
@ 2009-04-18 18:10                 ` Russell King - ARM Linux
       [not found]                   ` <20090418181030.GC1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
  0 siblings, 1 reply; 9+ messages in thread
From: Russell King - ARM Linux @ 2009-04-18 18:10 UTC (permalink / raw)
  To: Mark Brown; +Cc: Jean Delvare, linux-arm-kernel, Ben Dooks, linux-i2c

On Sat, Apr 18, 2009 at 06:34:06PM +0100, Mark Brown wrote:
> On Sat, Apr 18, 2009 at 03:42:34PM +0100, Russell King - ARM Linux wrote:
> > On Sat, Apr 18, 2009 at 04:29:00PM +0200, Jean Delvare wrote:
> 
> > > > The PCON device on the LX platform is the heart of the platform,
> > > > managing the power, providing battery information, booting, suspend/
> > > > resume and keyboard services to the PXA CPU.
> 
> > > Nack. Really, people, please read the files you modify, it isn't that
> > > hard.
> 
> > Maybe you can suggest a better place for it?
> 
> drivers/mfd?

It's not a multifunction device.  It's a microcontroller.

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^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
       [not found]                   ` <20090418181030.GC1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
@ 2009-04-19 11:11                     ` Mark Brown
       [not found]                       ` <20090419111114.GA8569-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
  0 siblings, 1 reply; 9+ messages in thread
From: Mark Brown @ 2009-04-19 11:11 UTC (permalink / raw)
  To: Russell King - ARM Linux
  Cc: Jean Delvare, linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW,
	Ben Dooks, linux-i2c-u79uwXL29TY76Z2rM5mHXA

On Sat, Apr 18, 2009 at 07:10:30PM +0100, Russell King - ARM Linux wrote:
> On Sat, Apr 18, 2009 at 06:34:06PM +0100, Mark Brown wrote:

> > > Maybe you can suggest a better place for it?

> > drivers/mfd?

> It's not a multifunction device.  It's a microcontroller.

Surely that's just an implementation detail?  As I understand your
description the microcontroller is hiding the control interfaces of the
other things it controls so the function is pretty similar.

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
       [not found]                       ` <20090419111114.GA8569-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
@ 2009-04-20 12:18                         ` Russell King - ARM Linux
       [not found]                           ` <20090420121805.GE3653-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
  0 siblings, 1 reply; 9+ messages in thread
From: Russell King - ARM Linux @ 2009-04-20 12:18 UTC (permalink / raw)
  To: Mark Brown
  Cc: Jean Delvare, linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW,
	Ben Dooks, linux-i2c-u79uwXL29TY76Z2rM5mHXA

On Sun, Apr 19, 2009 at 12:11:14PM +0100, Mark Brown wrote:
> On Sat, Apr 18, 2009 at 07:10:30PM +0100, Russell King - ARM Linux wrote:
> > On Sat, Apr 18, 2009 at 06:34:06PM +0100, Mark Brown wrote:
> 
> > > > Maybe you can suggest a better place for it?
> 
> > > drivers/mfd?
> 
> > It's not a multifunction device.  It's a microcontroller.
> 
> Surely that's just an implementation detail?  As I understand your
> description the microcontroller is hiding the control interfaces of the
> other things it controls so the function is pretty similar.

No, it's a question of whether drivers/mfd is right.  The "shovel
everything that doesn't fit elsewhere into drivers/mfd" approach
is just creating yet another problem, just like drivers/i2c/chips
is percieved to be.  The only difference is that it becomes someone
elses problem.

I've a good mind to put it in arch/arm/mach-pxa/ purely as a way of
bringing this issue to a close - it's far from ideal having drivers
outside of the drivers/ tree, but if that's the way it has to be to
progress, so be it.

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver
       [not found]                           ` <20090420121805.GE3653-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
@ 2009-04-20 12:25                             ` Mark Brown
  0 siblings, 0 replies; 9+ messages in thread
From: Mark Brown @ 2009-04-20 12:25 UTC (permalink / raw)
  To: Russell King - ARM Linux
  Cc: Jean Delvare, linux-arm-kernel-xIg/pKzrS19vn6HldHNs0ANdhmdF6hFW,
	Ben Dooks, linux-i2c-u79uwXL29TY76Z2rM5mHXA

On Mon, Apr 20, 2009 at 01:18:05PM +0100, Russell King - ARM Linux wrote:
> On Sun, Apr 19, 2009 at 12:11:14PM +0100, Mark Brown wrote:

> > Surely that's just an implementation detail?  As I understand your
> > description the microcontroller is hiding the control interfaces of the
> > other things it controls so the function is pretty similar.

> No, it's a question of whether drivers/mfd is right.  The "shovel
> everything that doesn't fit elsewhere into drivers/mfd" approach
> is just creating yet another problem, just like drivers/i2c/chips
> is percieved to be.  The only difference is that it becomes someone
> elses problem.

Well, my thinking was that it looks like you've got a bunch of
subsystem-specific drivers for this chip with a core driver managing
shared resources like I/O with the device.  To my mind that's pretty
much the use case for MFD.

As far as general dumping grounds goes we already have drivers/misc.

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2009-04-20 12:25 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-04-18 14:19 [PATCH 0/5] PXA LX platform support Russell King - ARM Linux
     [not found] ` <20090418141932.GA1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
2009-04-18 14:20   ` [PATCH 1/5] [ARM] pxa: lx: add PCON i2c driver Russell King
     [not found]     ` <1240064452-14691-1-git-send-email-linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
2009-04-18 14:29       ` Jean Delvare
     [not found]         ` <20090418162900.0dc16531-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
2009-04-18 14:42           ` Russell King - ARM Linux
     [not found]             ` <20090418144234.GB1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
2009-04-18 17:34               ` Mark Brown
2009-04-18 18:10                 ` Russell King - ARM Linux
     [not found]                   ` <20090418181030.GC1236-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
2009-04-19 11:11                     ` Mark Brown
     [not found]                       ` <20090419111114.GA8569-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2009-04-20 12:18                         ` Russell King - ARM Linux
     [not found]                           ` <20090420121805.GE3653-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
2009-04-20 12:25                             ` Mark Brown

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