Currently gpio-hog doesn't work on gpio-mt7621 driver. On further
debugging, I noticed that set/clear register on this controller
only works on output pins. We need to setup pin direction before
writing values in bgpio_dir_out for a correct gpio-hog behavior.
This patchset introduces a new flag BGPIOF_NO_SET_ON_INPUT for
these kind of controller and set this flag for gpio-mt7621.
Chuanhong Guo (2):
gpio: mmio: introduce BGPIOF_NO_SET_ON_INPUT
gpio: mt7621: add BGPIOF_NO_SET_ON_INPUT flag
drivers/gpio/gpio-mmio.c | 23 +++++++++++++++++++----
drivers/gpio/gpio-mt7621.c | 4 ++--
include/linux/gpio/driver.h | 1 +
3 files changed, 22 insertions(+), 6 deletions(-)
--
2.24.1
Some gpio controllers ignores pin value writing when that pin is
configured as input mode. As a result, bgpio_dir_out should set
pin to output before configuring pin values or gpio pin values
can't be set up properly.
Introduce two variants of bgpio_dir_out: bgpio_dir_out_val_first
and bgpio_dir_out_dir_first, and assign direction_output according
to a new flag: BGPIOF_NO_SET_ON_INPUT.
Signed-off-by: Chuanhong Guo <[email protected]>
---
drivers/gpio/gpio-mmio.c | 23 +++++++++++++++++++----
include/linux/gpio/driver.h | 1 +
2 files changed, 20 insertions(+), 4 deletions(-)
diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c
index f729e3e9e983..b778f33cc6af 100644
--- a/drivers/gpio/gpio-mmio.c
+++ b/drivers/gpio/gpio-mmio.c
@@ -389,12 +389,10 @@ static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
return GPIO_LINE_DIRECTION_IN;
}
-static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+static void bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
{
unsigned long flags;
- gc->set(gc, gpio, val);
-
spin_lock_irqsave(&gc->bgpio_lock, flags);
gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
@@ -405,7 +403,21 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
gc->write_reg(gc->reg_dir_out, gc->bgpio_dir);
spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+}
+static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio,
+ int val)
+{
+ bgpio_dir_out(gc, gpio, val);
+ gc->set(gc, gpio, val);
+ return 0;
+}
+
+static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio,
+ int val)
+{
+ gc->set(gc, gpio, val);
+ bgpio_dir_out(gc, gpio, val);
return 0;
}
@@ -538,7 +550,10 @@ static int bgpio_setup_direction(struct gpio_chip *gc,
if (dirout || dirin) {
gc->reg_dir_out = dirout;
gc->reg_dir_in = dirin;
- gc->direction_output = bgpio_dir_out;
+ if (flags & BGPIOF_NO_SET_ON_INPUT)
+ gc->direction_output = bgpio_dir_out_dir_first;
+ else
+ gc->direction_output = bgpio_dir_out_val_first;
gc->direction_input = bgpio_dir_in;
gc->get_direction = bgpio_get_dir;
} else {
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 6ef05bccc0a6..ed65e00ee977 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -572,6 +572,7 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev,
#define BGPIOF_BIG_ENDIAN_BYTE_ORDER BIT(3)
#define BGPIOF_READ_OUTPUT_REG_SET BIT(4) /* reg_set stores output value */
#define BGPIOF_NO_OUTPUT BIT(5) /* only input */
+#define BGPIOF_NO_SET_ON_INPUT BIT(6)
int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hwirq);
--
2.24.1
DSET/DCLR registers only works on output pins. Add corresponding
BGPIOF_NO_SET_ON_INPUT flag to bgpio_init call to fix direction_out
behavior.
Signed-off-by: Chuanhong Guo <[email protected]>
---
drivers/gpio/gpio-mt7621.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpio/gpio-mt7621.c b/drivers/gpio/gpio-mt7621.c
index b992321bb852..82fb20dca53a 100644
--- a/drivers/gpio/gpio-mt7621.c
+++ b/drivers/gpio/gpio-mt7621.c
@@ -227,8 +227,8 @@ mediatek_gpio_bank_probe(struct device *dev,
ctrl = mtk->base + GPIO_REG_DCLR + (rg->bank * GPIO_BANK_STRIDE);
diro = mtk->base + GPIO_REG_CTRL + (rg->bank * GPIO_BANK_STRIDE);
- ret = bgpio_init(&rg->chip, dev, 4,
- dat, set, ctrl, diro, NULL, 0);
+ ret = bgpio_init(&rg->chip, dev, 4, dat, set, ctrl, diro, NULL,
+ BGPIOF_NO_SET_ON_INPUT);
if (ret) {
dev_err(dev, "bgpio_init() failed\n");
return ret;
--
2.24.1
Quoting Chuanhong Guo <[email protected]>:
> Currently gpio-hog doesn't work on gpio-mt7621 driver. On further
> debugging, I noticed that set/clear register on this controller
> only works on output pins. We need to setup pin direction before
> writing values in bgpio_dir_out for a correct gpio-hog behavior.
> This patchset introduces a new flag BGPIOF_NO_SET_ON_INPUT for
> these kind of controller and set this flag for gpio-mt7621.
>
> Chuanhong Guo (2):
> gpio: mmio: introduce BGPIOF_NO_SET_ON_INPUT
> gpio: mt7621: add BGPIOF_NO_SET_ON_INPUT flag
>
> drivers/gpio/gpio-mmio.c | 23 +++++++++++++++++++----
> drivers/gpio/gpio-mt7621.c | 4 ++--
> include/linux/gpio/driver.h | 1 +
> 3 files changed, 22 insertions(+), 6 deletions(-)
>
> --
> 2.24.1
Thanks Chuanhong for debugging the problem!
With this patch gpio-hog works again.
For the series:
Tested-by: René van Dorst <[email protected]>
Greats,
René
Hi,
On Sun, Mar 15, 2020 at 1:14 PM Chuanhong Guo <[email protected]> wrote:
>
> Currently gpio-hog doesn't work on gpio-mt7621 driver. On further
> debugging, I noticed that set/clear register on this controller
> only works on output pins. We need to setup pin direction before
> writing values in bgpio_dir_out for a correct gpio-hog behavior.
> This patchset introduces a new flag BGPIOF_NO_SET_ON_INPUT for
> these kind of controller and set this flag for gpio-mt7621.
>
> Chuanhong Guo (2):
> gpio: mmio: introduce BGPIOF_NO_SET_ON_INPUT
> gpio: mt7621: add BGPIOF_NO_SET_ON_INPUT flag
>
> drivers/gpio/gpio-mmio.c | 23 +++++++++++++++++++----
> drivers/gpio/gpio-mt7621.c | 4 ++--
> include/linux/gpio/driver.h | 1 +
> 3 files changed, 22 insertions(+), 6 deletions(-)
>
This series looks good to me.
Reviewed-by: Sergio Paracuellos <[email protected]>
Best regards,
Sergio Paracuellos
> --
> 2.24.1
>
niedz., 15 mar 2020 o 13:14 Chuanhong Guo <[email protected]> napisał(a):
>
> Some gpio controllers ignores pin value writing when that pin is
> configured as input mode. As a result, bgpio_dir_out should set
> pin to output before configuring pin values or gpio pin values
> can't be set up properly.
> Introduce two variants of bgpio_dir_out: bgpio_dir_out_val_first
> and bgpio_dir_out_dir_first, and assign direction_output according
> to a new flag: BGPIOF_NO_SET_ON_INPUT.
>
> Signed-off-by: Chuanhong Guo <[email protected]>
Patch applied with Rene's and Sergio's tags.
Bartosz
niedz., 15 mar 2020 o 13:14 Chuanhong Guo <[email protected]> napisał(a):
>
> DSET/DCLR registers only works on output pins. Add corresponding
> BGPIOF_NO_SET_ON_INPUT flag to bgpio_init call to fix direction_out
> behavior.
>
> Signed-off-by: Chuanhong Guo <[email protected]>
Patch applied with Rene's and Sergio's tags.
Bartosz