Re: [PATCH v1 1/1] gpio: gpio-wcove: Fix GPIO control register offset calculation
From: sathyanarayanan kuppuswamy
Date: Thu Jun 15 2017 - 16:53:39 EST
Hi Andy,
On 06/15/2017 02:06 AM, Andy Shevchenko wrote:
On Thu, Jun 15, 2017 at 12:39 AM,
<sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote:
From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
According to Whiskey Cove PMIC GPIO controller specification, for GPIO
pins 0-12, GPIO input and output register control address range from,
0x4e44-0x4e50 for GPIO outputs control register
0x4e51-0x4e5d for GPIO input control register
But, currently when calculating the GPIO register offsets in to_reg()
function, all GPIO pins in the same bank uses the same GPIO control
register address. This logic is incorrect. This patch fixes this
issue.
This patch also adds support to selectively skip register modification
for virtual GPIOs.
In case of Whiskey Cove PMIC, ACPI code may use up 94 virtual GPIOs.
These virtual GPIOs are used by the ACPI code as means to access various
non GPIO bits of PMIC. So for these virtual GPIOs, we don't need to
manipulate the physical GPIO pin register. A similar patch has been
merged recently by Hans for Crystal Cove PMIC GPIO driver. You can
find more details about it in Commit 9a752b4c9ab9 ("gpio: crystalcove:
Do not write regular gpio registers for virtual GPIOs")
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
Reported-by: Jukka Laitinen <jukka.laitinen@xxxxxxxxx>
It seems it should have a Fixes tag.
This issue exist from the first commit. Should I add fixes tag for it ?
static inline unsigned int to_reg(int gpio, enum ctrl_register reg_type)
{
unsigned int reg;
- int bank;
- if (gpio < BANK0_NR_PINS)
- bank = 0;
- else if (gpio < BANK0_NR_PINS + BANK1_NR_PINS)
- bank = 1;
- else
- bank = 2;
+ if (gpio >= WCOVE_GPIO_NUM)
+ return -EOPNOTSUPP;
How this can happen?
Whiskey Cove PMIC only has 13 real GPIO pins. But if you look at the
gpio chip configuration in gpio-wcove.c driver, ngpio value is set as 94.
wg->chip.ngpio = WCOVE_VGPIO_NUM; // 94
So, 0 < gpio index < 13 are real GPIOs and 13 <= gpio index < 94 are
virtual GPIOs. So for these virtual GPIOs we don't have any real
configuration registers in the hardware. That's why we should skip
register modifications for any GPIO pin index >= WCOVE_GPIO_NUM.
if (reg_type == CTRL_IN)
- reg = GPIO_IN_CTRL_BASE + bank;
+ /*
+ * GPIO input control registers
+ * (one per pin): 0x4e51 - 0x4e5d
+ */
Noise.
Will remove it.
+ reg = GPIO_IN_CTRL_BASE + gpio;
else
- reg = GPIO_OUT_CTRL_BASE + bank;
+ /* GPIO output control registers
+ * (one per pin): 0x4e44 - 0x4e50
+ */
Wrong multi-line comment and noise overall.
If you wish to leave the comments, put them on top of the function as
its description.
I will just remove it.
+ reg = GPIO_OUT_CTRL_BASE + gpio;
return reg;
}
@@ -145,7 +147,10 @@ static void wcove_update_irq_mask(struct wcove_gpio *wg, int gpio)
static void wcove_update_irq_ctrl(struct wcove_gpio *wg, int gpio)
{
- unsigned int reg = to_reg(gpio, CTRL_IN);
+ int reg = to_reg(gpio, CTRL_IN);
+
+ if (reg < 0)
+ return;
Since above comment this change would gone.
+ int reg = to_reg(gpio, CTRL_OUT);
+
+ if (reg < 0)
+ return 0;
- return regmap_write(wg->regmap, to_reg(gpio, CTRL_OUT),
- CTLO_INPUT_SET);
+ return regmap_write(wg->regmap, reg, CTLO_INPUT_SET);
Ditto.
+ int reg = to_reg(gpio, CTRL_OUT);
- return regmap_write(wg->regmap, to_reg(gpio, CTRL_OUT),
- CTLO_OUTPUT_SET | value);
+ if (reg < 0)
+ return 0;
+
+ return regmap_write(wg->regmap, reg, CTLO_OUTPUT_SET | value);
Ditto.
+ int ret, reg = to_reg(gpio, CTRL_OUT);
Don't fit such variable on one line.
+
+ if (reg < 0)
+ return 0;
- ret = regmap_read(wg->regmap, to_reg(gpio, CTRL_OUT), &val);
+ ret = regmap_read(wg->regmap, reg, &val);
This would gone after addressing first comment.
- int ret;
+ int ret, reg = to_reg(gpio, CTRL_IN);
+
+ if (reg < 0)
+ return 0;
- ret = regmap_read(wg->regmap, to_reg(gpio, CTRL_IN), &val);
+ ret = regmap_read(wg->regmap, reg, &val);
Ditto.
+ int reg = to_reg(gpio, CTRL_OUT);
+
+ if (reg < 0)
+ return;
if (value)
- regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 1, 1);
+ regmap_update_bits(wg->regmap, reg, 1, 1);
else
- regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 1, 0);
+ regmap_update_bits(wg->regmap, reg, 1, 0);
Ditto.
+ int reg = to_reg(gpio, CTRL_OUT);
+
+ if (reg < 0)
+ return 0;
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_DRIVE_OPEN_DRAIN:
- return regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT),
- CTLO_DRV_MASK, CTLO_DRV_OD);
+ return regmap_update_bits(wg->regmap, reg, CTLO_DRV_MASK,
+ CTLO_DRV_OD);
case PIN_CONFIG_DRIVE_PUSH_PULL:
- return regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT),
- CTLO_DRV_MASK, CTLO_DRV_CMOS);
+ return regmap_update_bits(wg->regmap, reg, CTLO_DRV_MASK,
+ CTLO_DRV_CMOS);
Ditto.
+ if (data->hwirq >= WCOVE_GPIO_NUM)
+ return 0;
+
How could it happen?
+ if (data->hwirq >= WCOVE_GPIO_NUM)
+ return;
Ditto.
+ if (data->hwirq >= WCOVE_GPIO_NUM)
+ return;
Ditto.
--
Sathyanarayanan Kuppuswamy
Linux kernel developer