[PATCH 1/4] ARM: S5P6440: Add locking to GPIO calls

[PATCH 1/4] ARM: S5P6440: Add locking to GPIO calls

[Ben Dooks]

Add the new locking calls to ensure that these are always exclusively
accessing the GPIO registers.

Fixes a possible race between two threads modifying the same GPIO bank,

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
---
 arch/arm/mach-s5p6440/gpio.c |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-s5p6440/gpio.c b/arch/arm/mach-s5p6440/gpio.c
index 262dc75..92efc05 100644
--- a/arch/arm/mach-s5p6440/gpio.c
+++ b/arch/arm/mach-s5p6440/gpio.c
@@ -46,6 +46,7 @@ static int s5p6440_gpiolib_rbank_4bit2_input(struct gpio_chip *chip,
 	void __iomem *base = ourchip->base;
 	void __iomem *regcon = base;
 	unsigned long con;
+	unsigned long flags;
 
 	switch (offset) {
 	case 6:
@@ -63,10 +64,14 @@ static int s5p6440_gpiolib_rbank_4bit2_input(struct gpio_chip *chip,
 		break;
 	}
 
+	s3c_gpio_lock(ourchip, flags);
+
 	con = __raw_readl(regcon);
 	con &= ~(0xf << con_4bit_shift(offset));
 	__raw_writel(con, regcon);
 
+	s3c_gpio_unlock(ourchip, flags);
+
 	return 0;
 }
 
@@ -78,6 +83,7 @@ static int s5p6440_gpiolib_rbank_4bit2_output(struct gpio_chip *chip,
 	void __iomem *regcon = base;
 	unsigned long con;
 	unsigned long dat;
+	unsigned long flags;
 	unsigned con_offset  = offset;
 
 	switch (con_offset) {
@@ -96,6 +102,8 @@ static int s5p6440_gpiolib_rbank_4bit2_output(struct gpio_chip *chip,
 		break;
 	}
 
+	s3c_gpio_lock(ourchip, flags);
+
 	con = __raw_readl(regcon);
 	con &= ~(0xf << con_4bit_shift(con_offset));
 	con |= 0x1 << con_4bit_shift(con_offset);
@@ -109,6 +117,8 @@ static int s5p6440_gpiolib_rbank_4bit2_output(struct gpio_chip *chip,
 	__raw_writel(con, regcon);
 	__raw_writel(dat, base + GPIODAT_OFF);
 
+	s3c_gpio_unlock(ourchip, flags);
+
 	return 0;
 }
 
@@ -117,6 +127,7 @@ int s5p6440_gpio_setcfg_4bit_rbank(struct s3c_gpio_chip *chip,
 {
 	void __iomem *reg = chip->base;
 	unsigned int shift;
+	unsigned long flags;
 	u32 con;
 
 	switch (off) {
@@ -142,11 +153,15 @@ int s5p6440_gpio_setcfg_4bit_rbank(struct s3c_gpio_chip *chip,
 		cfg <<= shift;
 	}
 
+	s3c_gpio_lock(chip, flags);
+
 	con = __raw_readl(reg);
 	con &= ~(0xf << shift);
 	con |= cfg;
 	__raw_writel(con, reg);
 
+	s3c_gpio_unlock(chip, flags);
+
 	return 0;
 }
 
-- 
1.6.3.3

[PATCH 2/4] ARM: SAMSUNG: Make ADC client SMP safe

[Ben Dooks]

Change local_irq disable calls to use spinlocks to ensure that the
ADC driver data is protected against multiple access..

Note, this does not protect the client's data, and the client should
ensure it does not make multiple calls to the ADC driver.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
---
 arch/arm/plat-samsung/adc.c |   26 ++++++++++++++++++++------
 1 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/arch/arm/plat-samsung/adc.c b/arch/arm/plat-samsung/adc.c
index 210030d..04d9521 100644
--- a/arch/arm/plat-samsung/adc.c
+++ b/arch/arm/plat-samsung/adc.c
@@ -66,6 +66,7 @@ struct adc_device {
 	struct s3c_adc_client	*cur;
 	struct s3c_adc_client	*ts_pend;
 	void __iomem		*regs;
+	spinlock_t		 lock;
 
 	unsigned int		 prescale;
 
@@ -74,7 +75,7 @@ struct adc_device {
 
 static struct adc_device *adc_dev;
 
-static LIST_HEAD(adc_pending);
+static LIST_HEAD(adc_pending);	/* protected by adc_device.lock */
 
 #define adc_dbg(_adc, msg...) dev_dbg(&(_adc)->pdev->dev, msg)
 
@@ -145,7 +146,7 @@ int s3c_adc_start(struct s3c_adc_client *client,
 	if (client->is_ts && adc->ts_pend)
 		return -EAGAIN;
 
-	local_irq_save(flags);
+	spin_lock_irqsave(&adc->lock, flags);
 
 	client->channel = channel;
 	client->nr_samples = nr_samples;
@@ -157,7 +158,8 @@ int s3c_adc_start(struct s3c_adc_client *client,
 
 	if (!adc->cur)
 		s3c_adc_try(adc);
-	local_irq_restore(flags);
+
+	spin_unlock_irqrestore(&adc->lock, flags);
 
 	return 0;
 }
@@ -237,6 +239,10 @@ EXPORT_SYMBOL_GPL(s3c_adc_register);
 
 void s3c_adc_release(struct s3c_adc_client *client)
 {
+	unsigned long flags;
+
+	spin_lock_irqsave(&adc_dev->lock, flags);
+
 	/* We should really check that nothing is in progress. */
 	if (adc_dev->cur == client)
 		adc_dev->cur = NULL;
@@ -255,6 +261,8 @@ void s3c_adc_release(struct s3c_adc_client *client)
 
 	if (adc_dev->cur == NULL)
 		s3c_adc_try(adc_dev);
+
+	spin_unlock_irqrestore(&adc_dev->lock, flags);
 	kfree(client);
 }
 EXPORT_SYMBOL_GPL(s3c_adc_release);
@@ -264,7 +272,6 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw)
 	struct adc_device *adc = pw;
 	struct s3c_adc_client *client = adc->cur;
 	enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data;
-	unsigned long flags;
 	unsigned data0, data1;
 
 	if (!client) {
@@ -296,12 +303,12 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw)
 		client->select_cb(client, 1);
 		s3c_adc_convert(adc);
 	} else {
-		local_irq_save(flags);
+		spin_lock(&adc->lock);
 		(client->select_cb)(client, 0);
 		adc->cur = NULL;
 
 		s3c_adc_try(adc);
-		local_irq_restore(flags);
+		spin_unlock(&adc->lock);
 	}
 
 exit:
@@ -326,6 +333,8 @@ static int s3c_adc_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
+	spin_lock_init(&adc->lock);
+
 	adc->pdev = pdev;
 	adc->prescale = S3C2410_ADCCON_PRSCVL(49);
 
@@ -407,13 +416,17 @@ static int __devexit s3c_adc_remove(struct platform_device *pdev)
 static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state)
 {
 	struct adc_device *adc = platform_get_drvdata(pdev);
+	unsigned long flags;
 	u32 con;
 
+	spin_lock_irqsave(&adc->lock, flags);
+
 	con = readl(adc->regs + S3C2410_ADCCON);
 	con |= S3C2410_ADCCON_STDBM;
 	writel(con, adc->regs + S3C2410_ADCCON);
 
 	disable_irq(adc->irq);
+	spin_unlock_irqrestore(&adc->lock, flags);
 	clk_disable(adc->clk);
 
 	return 0;
@@ -422,6 +435,7 @@ static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state)
 static int s3c_adc_resume(struct platform_device *pdev)
 {
 	struct adc_device *adc = platform_get_drvdata(pdev);
+	unsigned long flags;
 
 	clk_enable(adc->clk);
 	enable_irq(adc->irq);
-- 
1.6.3.3

[PATCH 3/4] ARM: SAMSUNG: Add support for interrupt wakeup-sources

[Ben Dooks]

Add support for wakeup-mask style interrupts that share a
single mask register for various different interrupts. This
registers a set of interrupt->bit mappings and the register
they belong to.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
---
 arch/arm/plat-samsung/Kconfig                    |    8 ++++
 arch/arm/plat-samsung/Makefile                   |    2 +
 arch/arm/plat-samsung/include/plat/wakeup-mask.h |   44 ++++++++++++++++++++
 arch/arm/plat-samsung/wakeup-mask.c              |   47 ++++++++++++++++++++++
 4 files changed, 101 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/plat-samsung/include/plat/wakeup-mask.h
 create mode 100644 arch/arm/plat-samsung/wakeup-mask.c

diff --git a/arch/arm/plat-samsung/Kconfig b/arch/arm/plat-samsung/Kconfig
index 229919e..75f1142 100644
--- a/arch/arm/plat-samsung/Kconfig
+++ b/arch/arm/plat-samsung/Kconfig
@@ -269,4 +269,12 @@ config SAMSUNG_PM_CHECK_CHUNKSIZE
 
 	  See <file:Documentation/arm/Samsung-S3C24XX/Suspend.txt>
 
+config SAMSUNG_WAKEMASK
+	bool "Support for wakeup mask to irq mapping"
+	depends on PM
+	help
+	  Compile support for wakeup-mask controls found on the S3C6400
+	  and above. This code allows a set of interrupt to wakeup-mask
+	  mappings. See <plat/wakeup-mask.h>
+
 endif
diff --git a/arch/arm/plat-samsung/Makefile b/arch/arm/plat-samsung/Makefile
index 4828849..fbd5d1c 100644
--- a/arch/arm/plat-samsung/Makefile
+++ b/arch/arm/plat-samsung/Makefile
@@ -58,6 +58,8 @@ obj-$(CONFIG_PM)		+= pm.o
 obj-$(CONFIG_PM)		+= pm-gpio.o
 obj-$(CONFIG_SAMSUNG_PM_CHECK)	+= pm-check.o
 
+obj-$(CONFIG_SAMSUNG_WAKEMASK)	+= wakeup-mask.o
+
 # PWM support
 
 obj-$(CONFIG_HAVE_PWM)		+= pwm.o
diff --git a/arch/arm/plat-samsung/include/plat/wakeup-mask.h b/arch/arm/plat-samsung/include/plat/wakeup-mask.h
new file mode 100644
index 0000000..43e4acd
--- /dev/null
+++ b/arch/arm/plat-samsung/include/plat/wakeup-mask.h
@@ -0,0 +1,44 @@
+/* arch/arm/plat-samsung/include/plat/wakeup-mask.h
+ *
+ * Copyright 2010 Ben Dooks <ben-linux@fluff.org>
+ *
+ * Support for wakeup mask interrupts on newer SoCs
+ *
+ * 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.
+ *
+*/
+
+#ifndef __PLAT_WAKEUP_MASK_H
+#define __PLAT_WAKEUP_MASK_H __file__
+
+/* if no irq yet defined, but still want to mask */
+#define NO_WAKEUP_IRQ (0x90000000)
+
+/**
+ * struct samsung_wakeup_mask - wakeup mask information
+ * @irq: The interrupt associated with this wakeup.
+ * @bit: The bit, as a (1 << bitno) controlling this source.
+ */ 
+struct samsung_wakeup_mask {
+	unsigned int	irq;
+	u32		bit;
+};
+
+/**
+ * samsung_sync_wakemask - sync wakeup mask information for pm
+ * @reg: The register that is used.
+ * @masks: The list of masks to use.
+ * @nr_masks: The number of entries pointed to buy @masks.
+ *
+ * Synchronise the wakeup mask information at suspend time from the list
+ * of interrupts and control bits in @masks. We do this at suspend time
+ * as overriding the relevant irq chips is harder and the register is only
+ * required to be correct before we enter sleep.
+ */
+extern void samsung_sync_wakemask(void __iomem *reg,
+				  struct samsung_wakeup_mask *masks,
+				  int nr_masks);
+
+#endif /* __PLAT_WAKEUP_MASK_H */
diff --git a/arch/arm/plat-samsung/wakeup-mask.c b/arch/arm/plat-samsung/wakeup-mask.c
new file mode 100644
index 0000000..2e09b6a
--- /dev/null
+++ b/arch/arm/plat-samsung/wakeup-mask.c
@@ -0,0 +1,47 @@
+/* arch/arm/plat-samsung/wakeup-mask.c
+ *
+ * Copyright 2010 Ben Dooks <ben-linux@fluff.org>
+ *
+ * Support for wakeup mask interrupts on newer SoCs
+ *
+ * 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.
+*/
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/sysdev.h>
+#include <linux/types.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <plat/wakeup-mask.h>
+#include <plat/pm.h>
+
+void samsung_sync_wakemask(void __iomem *reg,
+			   struct samsung_wakeup_mask *mask, int nr_mask)
+{
+	struct irq_desc *desc;
+	u32 val;
+
+	val = __raw_readl(reg);
+
+	for (; nr_mask > 0; nr_mask--, mask++) {
+		if (mask->irq == NO_WAKEUP_IRQ) {
+			val |= mask->bit;
+			continue;
+		}
+
+		desc = irq_to_desc(mask->irq);
+
+		/* bit of a liberty to read this directly from irq_desc. */
+		if (desc->wake_depth > 0)
+			val &= ~mask->bit;
+		else
+			val |= mask->bit;
+	}
+
+	printk(KERN_INFO "wakemask %08x => %08x\n", __raw_readl(reg), val);
+	__raw_writel(val, reg);
+}
-- 
1.6.3.3

[PATCH 4/4] ARM: S3C64XX: PM: Synchronise wakeup mask on suspend

[Ben Dooks]

Use the new wakeup mask synchronisation code to set the
relevant wakeup mask bits.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
---
 arch/arm/mach-s3c64xx/Kconfig |    1 +
 arch/arm/mach-s3c64xx/pm.c    |   20 ++++++++++++++++++++
 2 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-s3c64xx/Kconfig b/arch/arm/mach-s3c64xx/Kconfig
index 69e9fbf..d026bf4 100644
--- a/arch/arm/mach-s3c64xx/Kconfig
+++ b/arch/arm/mach-s3c64xx/Kconfig
@@ -7,6 +7,7 @@
 config PLAT_S3C64XX
 	bool
 	depends on ARCH_S3C64XX
+	select SAMSUNG_WAKEMASK
 	default y
 	help
 	  Base platform code for any Samsung S3C64XX device
diff --git a/arch/arm/mach-s3c64xx/pm.c b/arch/arm/mach-s3c64xx/pm.c
index b8ac459..79412f7 100644
--- a/arch/arm/mach-s3c64xx/pm.c
+++ b/arch/arm/mach-s3c64xx/pm.c
@@ -18,8 +18,11 @@
 #include <linux/io.h>
 
 #include <mach/map.h>
+#include <mach/irqs.h>
 
 #include <plat/pm.h>
+#include <plat/wakeup-mask.h>
+
 #include <mach/regs-sys.h>
 #include <mach/regs-gpio.h>
 #include <mach/regs-clock.h>
@@ -153,8 +156,25 @@ static void s3c64xx_cpu_suspend(void)
 	panic("sleep resumed to originator?");
 }
 
+/* mapping of interrupts to parts of the wakeup mask */
+static struct samsung_wakeup_mask wake_irqs[] = {
+	{ .irq = IRQ_RTC_ALARM,	.bit = S3C64XX_PWRCFG_RTC_ALARM_DISABLE, },
+	{ .irq = IRQ_RTC_TIC,	.bit = S3C64XX_PWRCFG_RTC_TICK_DISABLE, },
+	{ .irq = IRQ_PENDN,	.bit = S3C64XX_PWRCFG_TS_DISABLE, },
+	{ .irq = IRQ_HSMMC0,	.bit = S3C64XX_PWRCFG_MMC0_DISABLE, },
+	{ .irq = IRQ_HSMMC1,	.bit = S3C64XX_PWRCFG_MMC1_DISABLE, },
+	{ .irq = IRQ_HSMMC2,	.bit = S3C64XX_PWRCFG_MMC2_DISABLE, },
+	{ .irq = NO_WAKEUP_IRQ,	.bit = S3C64XX_PWRCFG_BATF_DISABLE},
+	{ .irq = NO_WAKEUP_IRQ,	.bit = S3C64XX_PWRCFG_MSM_DISABLE },
+	{ .irq = NO_WAKEUP_IRQ,	.bit = S3C64XX_PWRCFG_HSI_DISABLE },
+	{ .irq = NO_WAKEUP_IRQ,	.bit = S3C64XX_PWRCFG_MSM_DISABLE },
+};
+
 static void s3c64xx_pm_prepare(void)
 {
+	samsung_sync_wakemask(S3C64XX_PWR_CFG,
+			      wake_irqs, ARRAY_SIZE(wake_irqs));
+
 	/* store address of resume. */
 	__raw_writel(virt_to_phys(s3c_cpu_resume), S3C64XX_INFORM0);
 
-- 
1.6.3.3