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>
diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c
index f01c336..6012c4e 100644
--- a/drivers/w1/masters/w1-gpio.c
+++ b/drivers/w1/masters/w1-gpio.c
@@ -104,6 +104,13 @@
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 @@
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 @@
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);