pinctrl: samsung: Fix NULL pointer exception on external interrupts on S3C24xx

After commit 8b1bd11c1f8f ("pinctrl: samsung: Add the support the
multiple IORESOURCE_MEM for one pin-bank"), the S3C24xx (and probably
S3C64xx as well) fails:

	Unable to handle kernel NULL pointer dereference at virtual address 000000a8
	...
	(s3c24xx_demux_eint4_7) from [<c004469c>] (__handle_domain_irq+0x6c/0xcc)
	(__handle_domain_irq) from [<c0009444>] (s3c24xx_handle_irq+0x6c/0x12c)
	(s3c24xx_handle_irq) from [<c000e5fc>] (__irq_svc+0x5c/0x78)

Mentioned commit moved the pointer to controller's base IO memory address
from each controller's driver data (samsung_pinctrl_drv_data) to per-bank
structure (samsung_pin_bank).  The external interrupt demux
handlers (s3c24xx_demux_eint()) tried to get this base address from opaque
pointer stored under irq_chip data:

	struct irq_data *irqd = irq_desc_get_irq_data(desc);
	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd);
	...
	pend = readl(bank->eint_base + EINTPEND_REG);

which is wrong because this is hardware irq and it bank was never set
for this irq_chip.

For S3C24xx and S3C64xx, this partially reverts mentioned commit by
bringing back the virt_base stored under each controller's driver data
(samsung_pinctrl_drv_data).  This virt_base address will be now
duplicated:
 - samsung_pinctrl_drv_data->virt_base: used on S3C24xx and S3C64xx,
 - samsung_pin_bank->pctl_base: used on Exynos.

Fixes: 8b1bd11c1f8f ("pinctrl: samsung: Add the support the multiple IORESOURCE_MEM for one pin-bank")
Cc: <stable@vger.kernel.org>
Cc: Sergio Prado <sergio.prado@e-labworks.com>
Reported-by: Sergio Prado <sergio.prado@e-labworks.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Lihua Yao <ylhuajnu@163.com>

1 files changed, 21 insertions, 16 deletions

diff --git a/drivers/pinctrl/samsung/pinctrl-s3c24xx.c b/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
index 49774851e84a..edf27264b603 100644
--- a/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
+++ b/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
@@ -151,7 +151,7 @@ static void s3c24xx_eint_set_function(struct samsung_pinctrl_drv_data *d,
 	u32 val;
 
 	/* Make sure that pin is configured as interrupt */
-	reg = bank->pctl_base + bank->pctl_offset;
+	reg = d->virt_base + bank->pctl_offset;
 	shift = pin * bank_type->fld_width[PINCFG_TYPE_FUNC];
 	mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
 
@@ -184,7 +184,7 @@ static int s3c24xx_eint_type(struct irq_data *data, unsigned int type)
 	s3c24xx_eint_set_handler(data, type);
 
 	/* Set up interrupt trigger */
-	reg = bank->eint_base + EINT_REG(index);
+	reg = d->virt_base + EINT_REG(index);
 	shift = EINT_OFFS(index);
 
 	val = readl(reg);
@@ -259,29 +259,32 @@ static void s3c2410_demux_eint0_3(struct irq_desc *desc)
 static void s3c2412_eint0_3_ack(struct irq_data *data)
 {
 	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(data);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
 
 	unsigned long bitval = 1UL << data->hwirq;
-	writel(bitval, bank->eint_base + EINTPEND_REG);
+	writel(bitval, d->virt_base + EINTPEND_REG);
 }
 
 static void s3c2412_eint0_3_mask(struct irq_data *data)
 {
 	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(data);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
 	unsigned long mask;
 
-	mask = readl(bank->eint_base + EINTMASK_REG);
+	mask = readl(d->virt_base + EINTMASK_REG);
 	mask |= (1UL << data->hwirq);
-	writel(mask, bank->eint_base + EINTMASK_REG);
+	writel(mask, d->virt_base + EINTMASK_REG);
 }
 
 static void s3c2412_eint0_3_unmask(struct irq_data *data)
 {
 	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(data);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
 	unsigned long mask;
 
-	mask = readl(bank->eint_base + EINTMASK_REG);
+	mask = readl(d->virt_base + EINTMASK_REG);
 	mask &= ~(1UL << data->hwirq);
-	writel(mask, bank->eint_base + EINTMASK_REG);
+	writel(mask, d->virt_base + EINTMASK_REG);
 }
 
 static struct irq_chip s3c2412_eint0_3_chip = {
@@ -316,31 +319,34 @@ static void s3c2412_demux_eint0_3(struct irq_desc *desc)
 static void s3c24xx_eint_ack(struct irq_data *data)
 {
 	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(data);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
 	unsigned char index = bank->eint_offset + data->hwirq;
 
-	writel(1UL << index, bank->eint_base + EINTPEND_REG);
+	writel(1UL << index, d->virt_base + EINTPEND_REG);
 }
 
 static void s3c24xx_eint_mask(struct irq_data *data)
 {
 	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(data);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
 	unsigned char index = bank->eint_offset + data->hwirq;
 	unsigned long mask;
 
-	mask = readl(bank->eint_base + EINTMASK_REG);
+	mask = readl(d->virt_base + EINTMASK_REG);
 	mask |= (1UL << index);
-	writel(mask, bank->eint_base + EINTMASK_REG);
+	writel(mask, d->virt_base + EINTMASK_REG);
 }
 
 static void s3c24xx_eint_unmask(struct irq_data *data)
 {
 	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(data);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
 	unsigned char index = bank->eint_offset + data->hwirq;
 	unsigned long mask;
 
-	mask = readl(bank->eint_base + EINTMASK_REG);
+	mask = readl(d->virt_base + EINTMASK_REG);
 	mask &= ~(1UL << index);
-	writel(mask, bank->eint_base + EINTMASK_REG);
+	writel(mask, d->virt_base + EINTMASK_REG);
 }
 
 static struct irq_chip s3c24xx_eint_chip = {
@@ -356,14 +362,13 @@ static inline void s3c24xx_demux_eint(struct irq_desc *desc,
 {
 	struct s3c24xx_eint_data *data = irq_desc_get_handler_data(desc);
 	struct irq_chip *chip = irq_desc_get_chip(desc);
-	struct irq_data *irqd = irq_desc_get_irq_data(desc);
-	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd);
+	struct samsung_pinctrl_drv_data *d = data->drvdata;
 	unsigned int pend, mask;
 
 	chained_irq_enter(chip, desc);
 
-	pend = readl(bank->eint_base + EINTPEND_REG);
-	mask = readl(bank->eint_base + EINTMASK_REG);
+	pend = readl(d->virt_base + EINTPEND_REG);
+	mask = readl(d->virt_base + EINTMASK_REG);
 
 	pend &= ~mask;
 	pend &= range;