summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorGuan Ben <ben.guan@cn.bosch.com>2017-02-07 08:22:04 +0300
committerSamuel Ortiz <sameo@linux.intel.com>2017-04-02 01:32:34 +0300
commitce69b95ca4e459f54b5afad717d2129d3ba1ff6e (patch)
tree4f5461fbdac5ca2bd52c7f836560a65f35cddcf8
parent96bd0b5e550f26e8472c624d1aabe7448d0a7c27 (diff)
downloadlinux-ce69b95ca4e459f54b5afad717d2129d3ba1ff6e.tar.xz
NFC: Make EN2 pin optional in the TRF7970A driver
Make the EN2 pin optional. This is useful for boards, which have this pin fix wired, for example to ground. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Guan Ben <ben.guan@cn.bosch.com> Signed-off-by: Mark Jonas <mark.jonas@de.bosch.com> Signed-off-by: Heiko Schocher <hs@denx.de> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
-rw-r--r--Documentation/devicetree/bindings/net/nfc/trf7970a.txt4
-rw-r--r--drivers/nfc/trf7970a.c26
2 files changed, 16 insertions, 14 deletions
diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
index 32b35a07abe4..5889a3d133b2 100644
--- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
+++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
@@ -5,8 +5,8 @@ Required properties:
- spi-max-frequency: Maximum SPI frequency (<= 2000000).
- interrupt-parent: phandle of parent interrupt handler.
- interrupts: A single interrupt specifier.
-- ti,enable-gpios: Two GPIO entries used for 'EN' and 'EN2' pins on the
- TRF7970A.
+- ti,enable-gpios: One or two GPIO entries used for 'EN' and 'EN2' pins on the
+ TRF7970A. EN2 is optional.
- vin-supply: Regulator for supply voltage to VIN pin
Optional SoC Specific Properties:
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 26c9dbbccb0c..75079fb16f22 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -1885,8 +1885,10 @@ static int trf7970a_power_up(struct trf7970a *trf)
usleep_range(5000, 6000);
if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
- gpio_set_value(trf->en2_gpio, 1);
- usleep_range(1000, 2000);
+ if (gpio_is_valid(trf->en2_gpio)) {
+ gpio_set_value(trf->en2_gpio, 1);
+ usleep_range(1000, 2000);
+ }
}
gpio_set_value(trf->en_gpio, 1);
@@ -1914,7 +1916,8 @@ static int trf7970a_power_down(struct trf7970a *trf)
}
gpio_set_value(trf->en_gpio, 0);
- gpio_set_value(trf->en2_gpio, 0);
+ if (gpio_is_valid(trf->en2_gpio))
+ gpio_set_value(trf->en2_gpio, 0);
ret = regulator_disable(trf->regulator);
if (ret)
@@ -2032,15 +2035,14 @@ static int trf7970a_probe(struct spi_device *spi)
trf->en2_gpio = of_get_named_gpio(np, "ti,enable-gpios", 1);
if (!gpio_is_valid(trf->en2_gpio)) {
- dev_err(trf->dev, "No EN2 GPIO property\n");
- return trf->en2_gpio;
- }
-
- ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
- GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN2");
- if (ret) {
- dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
- return ret;
+ dev_info(trf->dev, "No EN2 GPIO property\n");
+ } else {
+ ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
+ GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN2");
+ if (ret) {
+ dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
+ return ret;
+ }
}
if (of_property_read_bool(np, "en2-rf-quirk"))