| Message ID | 1402977500-19987-3-git-send-email-george.cherian@ti.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Tue, Jun 17, 2014 at 04:58:20AM +0100, George Cherian wrote: > Add device tree support to extcon-gpio driver. > Add devicetree binding documentation > > Signed-off-by: George Cherian <george.cherian@ti.com> > --- > .../devicetree/bindings/extcon/extcon-gpio.txt | 34 ++++++++++++++++++++++ > drivers/extcon/extcon-gpio.c | 29 ++++++++++++++++++ > 2 files changed, 63 insertions(+) > create mode 100644 Documentation/devicetree/bindings/extcon/extcon-gpio.txt > > diff --git a/Documentation/devicetree/bindings/extcon/extcon-gpio.txt b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt > new file mode 100644 > index 0000000..80b791b > --- /dev/null > +++ b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt > @@ -0,0 +1,34 @@ > +GPIO based EXTCON > + > +EXTCON GPIO > +----------- > + > +Required Properties: > + - compatible: should be: > + * "ti,extcon-gpio" > + - gpios: specifies the gpio pin used. > + - debounce: Debounce time for GPIO IRQ in ms > + - irq-flags: IRQ flag to be used ( eg: IRQ_TYPE_EDGE_FALLING) This looks distinctly odd. Why do you need this here? > +Optional Properties: > + - gpio-active-low: Property describing whether gpio active state is 1 or 0 > + If defined , low state of gpio means active. Surely this is defined in the gpio flags? > + - check-on-resume: Property describing whether to check the gpio state > + while resuming from SLEEP. Does this need to be in DT? Surely we could jsut always check this? > + - state-on: print_state is overriden with state_on string if provided. > + If NULL, default method of extcon class is used. > + - state_off: print_state is overriden with state_off string if provided. > + If NUll, default method of extcon class is used. This means nothing from a HW perspective. This describes linux internal details. [...] > + of_property_read_u32(np, "debounce", (u32 *)&pdata->debounce); > + of_property_read_u32(np, "irq-flags", (u32 *)&pdata->irq_flags); If you need theses casts, the code is broken. These functions can only read into a u32. If you pass a smaller type you'll trash aribtrary memory locations, and if you pass a larger type this is broken for BE. Mark. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 6/17/2014 9:27 PM, Mark Rutland wrote: > On Tue, Jun 17, 2014 at 04:58:20AM +0100, George Cherian wrote: >> Add device tree support to extcon-gpio driver. >> Add devicetree binding documentation >> >> Signed-off-by: George Cherian <george.cherian@ti.com> >> --- >> .../devicetree/bindings/extcon/extcon-gpio.txt | 34 ++++++++++++++++++++++ >> drivers/extcon/extcon-gpio.c | 29 ++++++++++++++++++ >> 2 files changed, 63 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/extcon/extcon-gpio.txt >> >> diff --git a/Documentation/devicetree/bindings/extcon/extcon-gpio.txt b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt >> new file mode 100644 >> index 0000000..80b791b >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt >> @@ -0,0 +1,34 @@ >> +GPIO based EXTCON >> + >> +EXTCON GPIO >> +----------- >> + >> +Required Properties: >> + - compatible: should be: >> + * "ti,extcon-gpio" >> + - gpios: specifies the gpio pin used. >> + - debounce: Debounce time for GPIO IRQ in ms >> + - irq-flags: IRQ flag to be used ( eg: IRQ_TYPE_EDGE_FALLING) > This looks distinctly odd. Why do you need this here? The driver takes this as part of platform data. It never continues operation if an invalid irq-flag is supplied. Also these can be used for different SoC's whose GPIO's might support IRQ_TYPE_EDGE_FALLING/RISING. Now since this is based on gpio we cant up front give a seperate "interrupts = " property, since we dont know the gpio-pin irq number. Chanwoo any comments? > >> +Optional Properties: >> + - gpio-active-low: Property describing whether gpio active state is 1 or 0 >> + If defined , low state of gpio means active. > Surely this is defined in the gpio flags? Yes, I will make necessary changes. > >> + - check-on-resume: Property describing whether to check the gpio state >> + while resuming from SLEEP. > Does this need to be in DT? Surely we could jsut always check this? okay. For my use-case I dont need this. Chanwoo, any comments? >> + - state-on: print_state is overriden with state_on string if provided. >> + If NULL, default method of extcon class is used. >> + - state_off: print_state is overriden with state_off string if provided. >> + If NUll, default method of extcon class is used. > This means nothing from a HW perspective. This describes linux internal > details. You mean to say this should not be part of dt? > [...] > >> + of_property_read_u32(np, "debounce", (u32 *)&pdata->debounce); >> + of_property_read_u32(np, "irq-flags", (u32 *)&pdata->irq_flags); > If you need theses casts, the code is broken. I dont need this, will remove in v2. > > These functions can only read into a u32. If you pass a smaller type > you'll trash aribtrary memory locations, and if you pass a larger type > this is broken for BE. true. > Mark.
diff --git a/Documentation/devicetree/bindings/extcon/extcon-gpio.txt b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt new file mode 100644 index 0000000..80b791b --- /dev/null +++ b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt @@ -0,0 +1,34 @@ +GPIO based EXTCON + +EXTCON GPIO +----------- + +Required Properties: + - compatible: should be: + * "ti,extcon-gpio" + - gpios: specifies the gpio pin used. + - debounce: Debounce time for GPIO IRQ in ms + - irq-flags: IRQ flag to be used ( eg: IRQ_TYPE_EDGE_FALLING) + +Optional Properties: + - gpio-active-low: Property describing whether gpio active state is 1 or 0 + If defined , low state of gpio means active. + - check-on-resume: Property describing whether to check the gpio state + while resuming from SLEEP. + - state-on: print_state is overriden with state_on string if provided. + If NULL, default method of extcon class is used. + - state_off: print_state is overriden with state_off string if provided. + If NUll, default method of extcon class is used. + +Eg: + + extcon1: am43_usbid_extcon1 { + compatible = "ti,extcon-gpio"; + gpios = <&gpio3 12 GPIO_ACTIVE_HIGH>; + gpio-active-low; + debounce = <20>; + irq-flags = <IRQ_TYPE_EDGE_FALLING>; + state-on = "USB ID FLOAT"; + state-off = "USB ID GND"; + + }; diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c index 6c268b4..14d999d 100644 --- a/drivers/extcon/extcon-gpio.c +++ b/drivers/extcon/extcon-gpio.c @@ -27,6 +27,7 @@ #include <linux/interrupt.h> #include <linux/kernel.h> #include <linux/module.h> +#include <linux/of_gpio.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/workqueue.h> @@ -83,12 +84,34 @@ static ssize_t extcon_gpio_print_state(struct extcon_dev *edev, char *buf) static int gpio_extcon_probe(struct platform_device *pdev) { + struct device_node *np = pdev->dev.of_node; struct gpio_extcon_platform_data *pdata = dev_get_platdata(&pdev->dev); struct gpio_extcon_data *extcon_data; int ret; + if (np) { + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + pdata->gpio = of_get_gpio(np, 0); + if (!gpio_is_valid(pdata->gpio)) + return -EPROBE_DEFER; + + pdata->name = np->name; + pdata->gpio_active_low = of_property_read_bool(np, + "gpio-active-low"); + pdata->check_on_resume = of_property_read_bool(np, + "check-on-resume"); + of_property_read_u32(np, "debounce", (u32 *)&pdata->debounce); + of_property_read_u32(np, "irq-flags", (u32 *)&pdata->irq_flags); + of_property_read_string(np, "state-on", &pdata->state_on); + of_property_read_string(np, "state-off", &pdata->state_off); + } + if (!pdata) return -EBUSY; + if (!pdata->irq_flags) { dev_err(&pdev->dev, "IRQ flag is not specified.\n"); return -EINVAL; @@ -177,6 +200,11 @@ static int gpio_extcon_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops, NULL, gpio_extcon_resume); +static struct of_device_id of_extcon_gpio_match_tbl[] = { + { .compatible = "ti,extcon-gpio", }, + { /* end */ } +}; + static struct platform_driver gpio_extcon_driver = { .probe = gpio_extcon_probe, .remove = gpio_extcon_remove, @@ -184,6 +212,7 @@ static struct platform_driver gpio_extcon_driver = { .name = "extcon-gpio", .owner = THIS_MODULE, .pm = &gpio_extcon_pm_ops, + .of_match_table = of_extcon_gpio_match_tbl, }, };
Add device tree support to extcon-gpio driver. Add devicetree binding documentation Signed-off-by: George Cherian <george.cherian@ti.com> --- .../devicetree/bindings/extcon/extcon-gpio.txt | 34 ++++++++++++++++++++++ drivers/extcon/extcon-gpio.c | 29 ++++++++++++++++++ 2 files changed, 63 insertions(+) create mode 100644 Documentation/devicetree/bindings/extcon/extcon-gpio.txt