diff options
| author | Alan Tull <atull@kernel.org> | 2017-10-11 11:34:44 -0500 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2017-10-19 22:32:38 +0200 |
| commit | 07901a94f9f9b11cc3a4537e33229cb7e7df5d2a (patch) | |
| tree | b75c4dd6720c820e693b63b6d75abb662097f5f0 | |
| parent | f76a2d9d7f9524c54dfd9c7b49ed26e488c4cf6c (diff) | |
gpio: gpio-dwapb: add optional reset
Some platforms require reset to be released to allow register
access.
Signed-off-by: Alan Tull <atull@kernel.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
[Added DT bindings oneliner for standard reset binding]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt | 1 | ||||
| -rw-r--r-- | drivers/gpio/gpio-dwapb.c | 9 |
2 files changed, 10 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt b/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt index 4d6c8cdc8586..4a75da7051bd 100644 --- a/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt +++ b/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt @@ -29,6 +29,7 @@ controller. - interrupts : The interrupt to the parent controller raised when GPIOs generate the interrupts. - snps,nr-gpios : The number of pins in the port, a single cell. +- resets : Reset line for the controller. Example: diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c index 5cdb7bc3ad99..d782ad195c89 100644 --- a/drivers/gpio/gpio-dwapb.c +++ b/drivers/gpio/gpio-dwapb.c @@ -25,6 +25,7 @@ #include <linux/of_irq.h> #include <linux/platform_device.h> #include <linux/property.h> +#include <linux/reset.h> #include <linux/spinlock.h> #include <linux/platform_data/gpio-dwapb.h> #include <linux/slab.h> @@ -98,6 +99,7 @@ struct dwapb_gpio { unsigned int nr_ports; struct irq_domain *domain; unsigned int flags; + struct reset_control *rst; }; static inline u32 gpio_reg_v2_convert(unsigned int offset) @@ -629,6 +631,12 @@ static int dwapb_gpio_probe(struct platform_device *pdev) gpio->dev = &pdev->dev; gpio->nr_ports = pdata->nports; + gpio->rst = devm_reset_control_get_optional_shared(dev, NULL); + if (IS_ERR(gpio->rst)) + return PTR_ERR(gpio->rst); + + reset_control_deassert(gpio->rst); + gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports, sizeof(*gpio->ports), GFP_KERNEL); if (!gpio->ports) @@ -680,6 +688,7 @@ static int dwapb_gpio_remove(struct platform_device *pdev) dwapb_gpio_unregister(gpio); dwapb_irq_teardown(gpio); + reset_control_assert(gpio->rst); return 0; } |