onewire: w1-gpio: add ext_pullup_enable pin in platform data

In the process of porting boards to devicetree implemenation, we should
keep information about external circuitry where they belong - the
individual drivers.

This patch adds a way to specify a GPIO to drive the (optional) external
pull-up logic, rather than using a function pointer for that.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Ville Syrjälä <syrjala@sci.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Daniel Mack 2012-07-25 22:54:29 +02:00 committed by Greg Kroah-Hartman
parent 5f3d1382e3
commit d2323cf773
2 changed files with 18 additions and 1 deletions

View File

@ -104,6 +104,13 @@ static int __init w1_gpio_probe(struct platform_device *pdev)
if (err)
goto free_master;
if (gpio_is_valid(pdata->ext_pullup_enable_pin)) {
err = gpio_request_one(pdata->ext_pullup_enable_pin,
GPIOF_INIT_LOW, "w1 pullup");
if (err < 0)
goto free_gpio;
}
master->data = pdata;
master->read_bit = w1_gpio_read_bit;
@ -117,15 +124,21 @@ static int __init w1_gpio_probe(struct platform_device *pdev)
err = w1_add_master_device(master);
if (err)
goto free_gpio;
goto free_gpio_ext_pu;
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(1);
if (gpio_is_valid(pdata->ext_pullup_enable_pin))
gpio_set_value(pdata->ext_pullup_enable_pin, 1);
platform_set_drvdata(pdev, master);
return 0;
free_gpio_ext_pu:
if (gpio_is_valid(pdata->ext_pullup_enable_pin))
gpio_free(pdata->ext_pullup_enable_pin);
free_gpio:
gpio_free(pdata->pin);
free_master:
@ -142,6 +155,9 @@ static int __exit w1_gpio_remove(struct platform_device *pdev)
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(0);
if (gpio_is_valid(pdata->ext_pullup_enable_pin))
gpio_set_value(pdata->ext_pullup_enable_pin, 0);
w1_remove_master_device(master);
gpio_free(pdata->pin);
kfree(master);

View File

@ -19,6 +19,7 @@ struct w1_gpio_platform_data {
unsigned int pin;
unsigned int is_open_drain:1;
void (*enable_external_pullup)(int enable);
unsigned int ext_pullup_enable_pin;
};
#endif /* _LINUX_W1_GPIO_H */