[v5] gpio: mmio: handle "ngpios" properly in bgpio_init()
Commit Message
bgpio_init() uses "sz" argument to populate ngpio, which is not
accurate. Instead, read the "ngpios" property from the DT and if it
doesn't exist, use the "sz" argument. With this change, drivers no
longer need to overwrite the ngpio variable after calling bgpio_init().
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
drivers/gpio/gpio-mmio.c | 9 +++++-
drivers/gpio/gpiolib.c | 68 ++++++++++++++++++++++------------------
drivers/gpio/gpiolib.h | 1 +
3 files changed, 46 insertions(+), 32 deletions(-)
Comments
On Mon, Jul 10, 2023 at 11:49 PM Asmaa Mnebhi <asmaa@nvidia.com> wrote:
>
> bgpio_init() uses "sz" argument to populate ngpio, which is not
> accurate. Instead, read the "ngpios" property from the DT and if it
> doesn't exist, use the "sz" argument. With this change, drivers no
> longer need to overwrite the ngpio variable after calling bgpio_init().
>
> Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> ---
Applied, thanks!
Bart
On Tue, Jul 18, 2023 at 9:18 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> On Mon, Jul 10, 2023 at 11:49 PM Asmaa Mnebhi <asmaa@nvidia.com> wrote:
...
> Applied, thanks!
This has a bug.
>
> > Applied, thanks!
>
> This has a bug.
>
My apologies for this inconvenience. This is not the right patch to be applied. It was rejected by Andy. I just forwarded to you the patch to apply.
Its only one patch an dis named:
[PATCH v2 1/1] gpio: mmio: handle "ngpios" properly in bgpio_init()
On Tue, Jul 18, 2023 at 8:39 PM Asmaa Mnebhi <asmaa@nvidia.com> wrote:
>
> >
> > > Applied, thanks!
> >
> > This has a bug.
> >
> My apologies for this inconvenience. This is not the right patch to be applied. It was rejected by Andy. I just forwarded to you the patch to apply.
> Its only one patch an dis named:
> [PATCH v2 1/1] gpio: mmio: handle "ngpios" properly in bgpio_init()
Yeah, I figured and backed it out.
Bart
@@ -60,6 +60,8 @@ o ` ~~~~\___/~~~~ ` controller in FPGA is ,.`
#include <linux/of.h>
#include <linux/of_device.h>
+#include "gpiolib.h"
+
static void bgpio_write8(void __iomem *reg, unsigned long data)
{
writeb(data, reg);
@@ -614,10 +616,15 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev,
gc->parent = dev;
gc->label = dev_name(dev);
gc->base = -1;
- gc->ngpio = gc->bgpio_bits;
gc->request = bgpio_request;
gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN);
+ ret = gpiochip_get_ngpios(gc, dev);
+ if (ret)
+ gc->ngpio = gc->bgpio_bits;
+ else
+ gc->bgpio_bits = round_up(gc->ngpio, 8);
+
ret = bgpio_setup_io(gc, dat, set, clr, flags);
if (ret)
return ret;
@@ -700,6 +700,40 @@ void *gpiochip_get_data(struct gpio_chip *gc)
}
EXPORT_SYMBOL_GPL(gpiochip_get_data);
+int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev)
+{
+ u32 ngpios = gc->ngpio;
+ int ret;
+
+ if (ngpios == 0) {
+ ret = device_property_read_u32(dev, "ngpios", &ngpios);
+ if (ret == -ENODATA)
+ /*
+ * -ENODATA means that there is no property found and
+ * we want to issue the error message to the user.
+ * Besides that, we want to return different error code
+ * to state that supplied value is not valid.
+ */
+ ngpios = 0;
+ else if (ret)
+ return ret;
+
+ gc->ngpio = ngpios;
+ }
+
+ if (gc->ngpio == 0) {
+ chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
+ return -EINVAL;
+ }
+
+ if (gc->ngpio > FASTPATH_NGPIO)
+ chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
+ gc->ngpio, FASTPATH_NGPIO);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gpiochip_get_ngpios);
+
int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
struct lock_class_key *lock_key,
struct lock_class_key *request_key)
@@ -707,7 +741,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
struct gpio_device *gdev;
unsigned long flags;
unsigned int i;
- u32 ngpios = 0;
int base = 0;
int ret = 0;
@@ -753,36 +786,9 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
else
gdev->owner = THIS_MODULE;
- /*
- * Try the device properties if the driver didn't supply the number
- * of GPIO lines.
- */
- ngpios = gc->ngpio;
- if (ngpios == 0) {
- ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
- if (ret == -ENODATA)
- /*
- * -ENODATA means that there is no property found and
- * we want to issue the error message to the user.
- * Besides that, we want to return different error code
- * to state that supplied value is not valid.
- */
- ngpios = 0;
- else if (ret)
- goto err_free_dev_name;
-
- gc->ngpio = ngpios;
- }
-
- if (gc->ngpio == 0) {
- chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
- ret = -EINVAL;
+ ret = gpiochip_get_ngpios(gc, &gdev->dev);
+ if (ret)
goto err_free_dev_name;
- }
-
- if (gc->ngpio > FASTPATH_NGPIO)
- chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
- gc->ngpio, FASTPATH_NGPIO);
gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL);
if (!gdev->descs) {
@@ -947,7 +953,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
/* failures here can mean systems won't boot... */
if (ret != -EPROBE_DEFER) {
pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
- base, base + (int)ngpios - 1,
+ base, base + (int)gc->ngpio - 1,
gc->label ? : "generic", ret);
}
return ret;
@@ -217,6 +217,7 @@ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce);
int gpiod_hog(struct gpio_desc *desc, const char *name,
unsigned long lflags, enum gpiod_flags dflags);
+int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev);
/*
* Return the GPIO number of the passed descriptor relative to its chip