pcf857x: support working w/o platform data

Provide sane defaults for pcf857x, so the driver can be used w/o providing
platform data (and thus can be simply bound via OF tree).

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 5 deletions

diff --git a/drivers/gpio/pcf857x.c b/drivers/gpio/pcf857x.c
index 29f19ce3e80..879b473aab5 100644
--- a/drivers/gpio/pcf857x.c
+++ b/drivers/gpio/pcf857x.c
@@ -190,7 +190,6 @@ static int pcf857x_probe(struct i2c_client *client,
         pdata = client->dev.platform_data;
         if (!pdata) {
                 dev_dbg(&client->dev, "no platform data\n");
-                return -EINVAL;
         }
 
         /* Allocate, initialize, and register this gpio_chip. */
@@ -200,7 +199,7 @@ static int pcf857x_probe(struct i2c_client *client,
 
         mutex_init(&gpio->lock);
 
-        gpio->chip.base = pdata->gpio_base;
+        gpio->chip.base = pdata ? pdata->gpio_base : -1;
         gpio->chip.can_sleep = 1;
         gpio->chip.dev = &client->dev;
         gpio->chip.owner = THIS_MODULE;
@@ -278,7 +277,7 @@ static int pcf857x_probe(struct i2c_client *client,
          * to zero, our software copy of the "latch" then matches the chip's
          * all-ones reset state.  Otherwise it flags pins to be driven low.
          */
-        gpio->out = ~pdata->n_latch;
+        gpio->out = pdata ? ~pdata->n_latch : ~0;
 
         status = gpiochip_add(&gpio->chip);
         if (status < 0)
@@ -299,7 +298,7 @@ static int pcf857x_probe(struct i2c_client *client,
         /* Let platform code set up the GPIOs and their users.
          * Now is the first time anyone could use them.
          */
-        if (pdata->setup) {
+        if (pdata && pdata->setup) {
                 status = pdata->setup(client,
                                 gpio->chip.base, gpio->chip.ngpio,
                                 pdata->context);
@@ -322,7 +321,7 @@ static int pcf857x_remove(struct i2c_client *client)
         struct pcf857x                  *gpio = i2c_get_clientdata(client);
         int                             status = 0;
 
-        if (pdata->teardown) {
+        if (pdata && pdata->teardown) {
                 status = pdata->teardown(client,
                                 gpio->chip.base, gpio->chip.ngpio,
                                 pdata->context);