| Message ID | 1435243557-7050-1-git-send-email-geert+renesas@glider.be (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
On Thu, Jun 25, 2015 at 4:45 PM, Geert Uytterhoeven <geert+renesas@glider.be> wrote: > Currently gpio modules are runtime-resumed at probe time. This means the > gpio module will be active all the time (except during system suspend, > if not configured as a wake-up source). > > While an R-Car Gen2 gpio module retains pins configured for output at > the requested level while put in standby mode, gpio registercannot be > accessed while suspended. Unfortunately pm_runtime_get_sync() cannot be > called from all contexts where gpio register access is needed. Hence > move the Runtime PM handling from probe/remove time to gpio request/free > time, which is probably the best we can do. > > On r8a7791/koelsch, gpio modules 0, 1, 3, and 4 are now suspended during > normal use (gpio2 is used for LEDs and regulators, gpio5 for keys, gpio6 > for SD-Card CD & WP, gpio7 for keys and regulators). > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Patch applied unless Magnus complains. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Linus, On Thu, Jul 16, 2015 at 5:43 PM, Linus Walleij <linus.walleij@linaro.org> wrote: > On Thu, Jun 25, 2015 at 4:45 PM, Geert Uytterhoeven > <geert+renesas@glider.be> wrote: > >> Currently gpio modules are runtime-resumed at probe time. This means the >> gpio module will be active all the time (except during system suspend, >> if not configured as a wake-up source). >> >> While an R-Car Gen2 gpio module retains pins configured for output at >> the requested level while put in standby mode, gpio registercannot be >> accessed while suspended. Unfortunately pm_runtime_get_sync() cannot be >> called from all contexts where gpio register access is needed. Hence >> move the Runtime PM handling from probe/remove time to gpio request/free >> time, which is probably the best we can do. >> >> On r8a7791/koelsch, gpio modules 0, 1, 3, and 4 are now suspended during >> normal use (gpio2 is used for LEDs and regulators, gpio5 for keys, gpio6 >> for SD-Card CD & WP, gpio7 for keys and regulators). >> >> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > > Patch applied unless Magnus complains. No complaints, just happy Magnus! Thanks, / magnus -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/gpio/gpio-rcar.c b/drivers/gpio/gpio-rcar.c index 29089ef6969fd33f..099a6f508f867821 100644 --- a/drivers/gpio/gpio-rcar.c +++ b/drivers/gpio/gpio-rcar.c @@ -251,17 +251,32 @@ static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip, static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset) { - return pinctrl_request_gpio(chip->base + offset); + struct gpio_rcar_priv *p = gpio_to_priv(chip); + int error; + + error = pm_runtime_get_sync(&p->pdev->dev); + if (error < 0) + return error; + + error = pinctrl_request_gpio(chip->base + offset); + if (error) + pm_runtime_put(&p->pdev->dev); + + return error; } static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset) { + struct gpio_rcar_priv *p = gpio_to_priv(chip); + pinctrl_free_gpio(chip->base + offset); /* Set the GPIO as an input to ensure that the next GPIO request won't * drive the GPIO pin as an output. */ gpio_rcar_config_general_input_output_mode(chip, offset, false); + + pm_runtime_put(&p->pdev->dev); } static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset) @@ -405,7 +420,6 @@ static int gpio_rcar_probe(struct platform_device *pdev) } pm_runtime_enable(dev); - pm_runtime_get_sync(dev); io = platform_get_resource(pdev, IORESOURCE_MEM, 0); irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); @@ -488,7 +502,6 @@ static int gpio_rcar_probe(struct platform_device *pdev) err1: gpiochip_remove(gpio_chip); err0: - pm_runtime_put(dev); pm_runtime_disable(dev); return ret; } @@ -499,7 +512,6 @@ static int gpio_rcar_remove(struct platform_device *pdev) gpiochip_remove(&p->gpio_chip); - pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev); return 0; }
Currently gpio modules are runtime-resumed at probe time. This means the gpio module will be active all the time (except during system suspend, if not configured as a wake-up source). While an R-Car Gen2 gpio module retains pins configured for output at the requested level while put in standby mode, gpio registercannot be accessed while suspended. Unfortunately pm_runtime_get_sync() cannot be called from all contexts where gpio register access is needed. Hence move the Runtime PM handling from probe/remove time to gpio request/free time, which is probably the best we can do. On r8a7791/koelsch, gpio modules 0, 1, 3, and 4 are now suspended during normal use (gpio2 is used for LEDs and regulators, gpio5 for keys, gpio6 for SD-Card CD & WP, gpio7 for keys and regulators). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- drivers/gpio/gpio-rcar.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)