The platform data in the dveice structure does not belong to the driver
and so it should not be trying to alter it, but instead use a local pointer
and populate it with a local copy in case we are dealing with device tree
setup.

Also allow mixed setups where platform data coexists with device tree and
prefer kernel-supplied data (it may be easier to fiddle in kernel structure
before committing final result to device tree).

Signed-off-by: Dmitry Torokhov <dmitry.torok...@gmail.com>
---
 drivers/w1/masters/w1-gpio.c | 93 +++++++++++++++++++++++++-------------------
 1 file changed, 53 insertions(+), 40 deletions(-)

diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c
index aa97a96..ee6b6e3 100644
--- a/drivers/w1/masters/w1-gpio.c
+++ b/drivers/w1/masters/w1-gpio.c
@@ -23,28 +23,33 @@
 #include "../w1.h"
 #include "../w1_int.h"
 
+struct w1_gpio {
+       struct w1_bus_master master;
+       const struct w1_gpio_platform_data *pdata;
+};
+
 static void w1_gpio_write_bit_dir(void *data, u8 bit)
 {
-       struct w1_gpio_platform_data *pdata = data;
+       struct w1_gpio *w1_gpio = data;
 
        if (bit)
-               gpio_direction_input(pdata->pin);
+               gpio_direction_input(w1_gpio->pdata->pin);
        else
-               gpio_direction_output(pdata->pin, 0);
+               gpio_direction_output(w1_gpio->pdata->pin, 0);
 }
 
 static void w1_gpio_write_bit_val(void *data, u8 bit)
 {
-       struct w1_gpio_platform_data *pdata = data;
+       struct w1_gpio *w1_gpio = data;
 
-       gpio_set_value(pdata->pin, bit);
+       gpio_set_value(w1_gpio->pdata->pin, bit);
 }
 
 static u8 w1_gpio_read_bit(void *data)
 {
-       struct w1_gpio_platform_data *pdata = data;
+       struct w1_gpio *w1_gpio = data;
 
-       return gpio_get_value(pdata->pin) ? 1 : 0;
+       return gpio_get_value(w1_gpio->pdata->pin) ? 1 : 0;
 }
 
 #ifdef CONFIG_OF
@@ -55,38 +60,43 @@ static struct of_device_id w1_gpio_dt_ids[] = {
 };
 MODULE_DEVICE_TABLE(of, w1_gpio_dt_ids);
 
-static int w1_gpio_probe_dt(struct platform_device *pdev)
+static struct w1_gpio_platform_data *
+w1_gpio_probe_dt(struct platform_device *pdev)
 {
-       struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+       struct w1_gpio_platform_data *pdata;
        struct device_node *np = pdev->dev.of_node;
 
+       if (!np)
+               return ERR_PTR(-ENOENT);
+
        pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
        if (!pdata)
-               return -ENOMEM;
+               return ERR_PTR(-ENOMEM);
 
        if (of_get_property(np, "linux,open-drain", NULL))
                pdata->is_open_drain = 1;
 
        pdata->pin = of_get_gpio(np, 0);
        pdata->ext_pullup_enable_pin = of_get_gpio(np, 1);
-       pdev->dev.platform_data = pdata;
 
-       return 0;
+       return pdata;
 }
 
 #else
 
-static inline int w1_gpio_probe_dt(struct platform_device *pdev)
+static inline struct w1_gpio_platform_data *
+w1_gpio_probe_dt(struct platform_device *pdev)
 {
-       return -ENOSYS;
+       return NULL;
 }
 
 #endif
 
 static int w1_gpio_probe(struct platform_device *pdev)
 {
-       struct w1_bus_master *master;
-       struct w1_gpio_platform_data *pdata;
+       const struct w1_gpio_platform_data *pdata =
+                                       dev_get_platdata(&pdev->dev);
+       struct w1_gpio *w1_gpio;
        struct pinctrl *pinctrl;
        int err;
 
@@ -94,23 +104,20 @@ static int w1_gpio_probe(struct platform_device *pdev)
        if (IS_ERR(pinctrl))
                dev_warn(&pdev->dev, "unable to select pin group\n");
 
-       if (of_have_populated_dt()) {
-               err = w1_gpio_probe_dt(pdev);
-               if (err < 0) {
-                       dev_err(&pdev->dev, "Failed to parse DT\n");
-                       return err;
-               }
-       }
-
-       pdata = pdev->dev.platform_data;
+       if (!pdata)
+               pdata = w1_gpio_probe_dt(pdev);
 
        if (!pdata) {
                dev_err(&pdev->dev, "No configuration data\n");
                return -ENXIO;
+       } else if (IS_ERR(pdata)) {
+               err = PTR_ERR(pdata);
+               dev_err(&pdev->dev, "Failed to parse DT\n");
+               return err;
        }
 
-       master = kzalloc(sizeof(struct w1_bus_master), GFP_KERNEL);
-       if (!master) {
+       w1_gpio = kzalloc(sizeof(struct w1_gpio), GFP_KERNEL);
+       if (!w1_gpio) {
                dev_err(&pdev->dev, "Out of memory\n");
                return -ENOMEM;
        }
@@ -131,18 +138,20 @@ static int w1_gpio_probe(struct platform_device *pdev)
                }
        }
 
-       master->data = pdata;
-       master->read_bit = w1_gpio_read_bit;
+       w1_gpio->pdata = pdata;
+
+       w1_gpio->master.data = w1_gpio;
+       w1_gpio->master.read_bit = w1_gpio_read_bit;
 
        if (pdata->is_open_drain) {
                gpio_direction_output(pdata->pin, 1);
-               master->write_bit = w1_gpio_write_bit_val;
+               w1_gpio->master.write_bit = w1_gpio_write_bit_val;
        } else {
                gpio_direction_input(pdata->pin);
-               master->write_bit = w1_gpio_write_bit_dir;
+               w1_gpio->master.write_bit = w1_gpio_write_bit_dir;
        }
 
-       err = w1_add_master_device(master);
+       err = w1_add_master_device(&w1_gpio->master);
        if (err) {
                dev_err(&pdev->dev, "w1_add_master device failed\n");
                goto free_gpio_ext_pu;
@@ -154,7 +163,7 @@ static int w1_gpio_probe(struct platform_device *pdev)
        if (gpio_is_valid(pdata->ext_pullup_enable_pin))
                gpio_set_value(pdata->ext_pullup_enable_pin, 1);
 
-       platform_set_drvdata(pdev, master);
+       platform_set_drvdata(pdev, w1_gpio);
 
        return 0;
 
@@ -164,15 +173,15 @@ static int w1_gpio_probe(struct platform_device *pdev)
  free_gpio:
        gpio_free(pdata->pin);
  free_master:
-       kfree(master);
+       kfree(w1_gpio);
 
        return err;
 }
 
 static int w1_gpio_remove(struct platform_device *pdev)
 {
-       struct w1_bus_master *master = platform_get_drvdata(pdev);
-       struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+       struct w1_gpio *w1_gpio = platform_get_drvdata(pdev);
+       const struct w1_gpio_platform_data *pdata = w1_gpio->pdata;
 
        if (pdata->enable_external_pullup)
                pdata->enable_external_pullup(0);
@@ -180,9 +189,9 @@ static int w1_gpio_remove(struct platform_device *pdev)
        if (gpio_is_valid(pdata->ext_pullup_enable_pin))
                gpio_set_value(pdata->ext_pullup_enable_pin, 0);
 
-       w1_remove_master_device(master);
+       w1_remove_master_device(&w1_gpio->master);
        gpio_free(pdata->pin);
-       kfree(master);
+       kfree(w1_gpio);
 
        return 0;
 }
@@ -190,7 +199,9 @@ static int w1_gpio_remove(struct platform_device *pdev)
 #ifdef CONFIG_PM_SLEEP
 static int w1_gpio_suspend(struct device *dev)
 {
-       const struct w1_gpio_platform_data *pdata = dev_get_platdata(dev);
+       struct platform_device *pdev = to_platform_device(dev);
+       struct w1_gpio *w1_gpio = platform_get_drvdata(pdev);
+       const struct w1_gpio_platform_data *pdata = w1_gpio->pdata;
 
        if (pdata->enable_external_pullup)
                pdata->enable_external_pullup(0);
@@ -200,7 +211,9 @@ static int w1_gpio_suspend(struct device *dev)
 
 static int w1_gpio_resume(struct device *dev)
 {
-       const struct w1_gpio_platform_data *pdata = dev_get_platdata(dev);
+       struct platform_device *pdev = to_platform_device(dev);
+       struct w1_gpio *w1_gpio = platform_get_drvdata(pdev);
+       const struct w1_gpio_platform_data *pdata = w1_gpio->pdata;
 
        if (pdata->enable_external_pullup)
                pdata->enable_external_pullup(1);
-- 
1.7.11.7

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to