V4L/DVB (10167): sms1xxx: add support for inverted gpio

negative gpio values signify inverted polarity

Signed-off-by: Michael Krufky <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/dvb/siano/sms-cards.c

···
 	return &sms_boards[id];
 }
 
-static int sms_set_gpio(struct smscore_device_t *coredev, u32 pin, int enable)
+static int sms_set_gpio(struct smscore_device_t *coredev, int pin, int enable)
 {
-	int ret;
+	int lvl, ret;
+	u32 gpio;
 	struct smscore_gpio_config gpioconfig = {
 		.direction            = SMS_GPIO_DIRECTION_OUTPUT,
 		.pullupdown           = SMS_GPIO_PULLUPDOWN_NONE,
···
 	if (pin == 0)
 		return -EINVAL;
 
-	ret = smscore_configure_gpio(coredev, pin, &gpioconfig);
+	if (pin < 0) {
+		/* inverted gpio */
+		gpio = pin * -1;
+		lvl = enable ? 0 : 1;
+	} else {
+		gpio = pin;
+		lvl = enable ? 1 : 0;
+	}
 
+	ret = smscore_configure_gpio(coredev, gpio, &gpioconfig);
 	if (ret < 0)
 		return ret;
 
-	return smscore_set_gpio(coredev, pin, enable);
+	return smscore_set_gpio(coredev, gpio, lvl);
 }
 
 int sms_board_setup(struct smscore_device_t *coredev)