Currently, spi-s3c64xx.c needs "cs-gpio" chip select GPIO to be
defined under "controller-data" node under each slave node.
&spi_x {
cs-gpios <>;
...
slave_node {
controller-data {
cs-gpio = <>;
...
};
...
};
...
};
Where as, SPI core and many other drivers uses "cs-gpios" for
from device tree node.
Hence, make changes in spi-s3c64xx.c driver to make use of
"cs-gpios" from SPI node(parent) instead of "cs-gpio" defined in
slaves "controller-data"(child) node.
Also updates the Device tree Documentation.
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx>
Cc: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx>
Cc: Doug Anderson <dianders@xxxxxxxxxxxx>
---
Changes since v1:
1. fixed a compilation warning thus squashing the other patch into this.
2. Updated device tree description in spi-samsung.txt
.../devicetree/bindings/spi/spi-samsung.txt | 8 ++-
drivers/spi/spi-s3c64xx.c | 56 ++++++++++++--------
2 files changed, 38 insertions(+), 26 deletions(-)
diff --git a/Documentation/devicetree/bindings/spi/spi-samsung.txt b/Documentation/devicetree/bindings/spi/spi-samsung.txt
index 86aa061..13bfcb5 100644
--- a/Documentation/devicetree/bindings/spi/spi-samsung.txt
+++ b/Documentation/devicetree/bindings/spi/spi-samsung.txt
@@ -42,15 +42,13 @@ Optional Board Specific Properties:
- num-cs: Specifies the number of chip select lines supported. If
not specified, the default number of chip select lines is set to 1.
+- cs-gpios: should specify GPIOs used for chipselects (see spi-bus.txt)
+
SPI Controller specific data in SPI slave nodes:
- The spi slave nodes should provide the following information which is required
by the spi controller.
- - cs-gpio: A gpio specifier that specifies the gpio line used as
- the slave select line by the spi controller. The format of the gpio
- specifier depends on the gpio controller.
-
- samsung,spi-feedback-delay: The sampling phase shift to be applied on the
miso line (to account for any lag in the miso line). The following are the
valid values.
@@ -85,6 +83,7 @@ Example:
#size-cells = <0>;
pinctrl-names = "default";
pinctrl-0 = <&spi0_bus>;
+ cs-gpios = <&gpa2 5 1 0 3>;
w25q80bw@0 {
#address-cells = <1>;
@@ -94,7 +93,6 @@ Example:
spi-max-frequency = <10000>;
controller-data {
- cs-gpio = <&gpa2 5 1 0 3>;
samsung,spi-feedback-delay = <0>;
};
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 75a5696..4594dde 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -750,47 +750,56 @@ static int s3c64xx_spi_transfer_one(struct spi_master *master,
}
static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
- struct spi_device *spi)
+ struct spi_device *spi,
+ struct s3c64xx_spi_csinfo *cs)
{
- struct s3c64xx_spi_csinfo *cs;
- struct device_node *slave_np, *data_np = NULL;
- struct s3c64xx_spi_driver_data *sdd;
+ struct device_node *data_np = NULL;
u32 fb_delay = 0;
- sdd = spi_master_get_devdata(spi->master);
- slave_np = spi->dev.of_node;
- if (!slave_np) {
- dev_err(&spi->dev, "device node not found\n");
+ data_np = of_get_child_by_name(spi->dev.of_node, "controller-data");
+ if (!data_np) {
+ dev_err(&spi->dev, "child node 'controller-data' not found\n");
return ERR_PTR(-EINVAL);
}
- data_np = of_get_child_by_name(slave_np, "controller-data");
- if (!data_np) {
- dev_err(&spi->dev, "child node 'controller-data' not found\n");
+ of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
+ cs->fb_delay = fb_delay;
+ of_node_put(data_np);
+
+ return cs;
+}
+
+static struct s3c64xx_spi_csinfo *s3c64xx_get_cs_gpios(struct spi_device *spi)
+{
+ struct device_node *parent_np = NULL;
+ struct s3c64xx_spi_driver_data *sdd;
+ struct s3c64xx_spi_csinfo *cs;
+
+ parent_np = of_get_parent(spi->dev.of_node);
+ if (!parent_np) {
+ dev_err(&spi->dev, "Parent node not found\n");
return ERR_PTR(-EINVAL);
}
+ sdd = spi_master_get_devdata(spi->master);
+
cs = kzalloc(sizeof(*cs), GFP_KERNEL);
if (!cs) {
- of_node_put(data_np);
+ of_node_put(parent_np);
return ERR_PTR(-ENOMEM);
}
/* The CS line is asserted/deasserted by the gpio pin */
if (sdd->cs_gpio)
- cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
+ cs->line = of_get_named_gpio(parent_np, "cs-gpios", 0);
if (!gpio_is_valid(cs->line)) {
dev_err(&spi->dev, "chip select gpio is not specified or invalid\n");
- kfree(cs);
- of_node_put(data_np);
+ of_node_put(parent_np);
return ERR_PTR(-EINVAL);
}
- of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
- cs->fb_delay = fb_delay;
- of_node_put(data_np);
- return cs;
+ return s3c64xx_get_slave_ctrldata(spi, cs);
}
/*
@@ -806,9 +815,14 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
struct s3c64xx_spi_info *sci;
int err;
+ if (!spi->dev.of_node) {
+ dev_err(&spi->dev, "device node not found\n");
+ return -EINVAL;
+ }
+
sdd = spi_master_get_devdata(spi->master);
if (!cs && spi->dev.of_node) {
- cs = s3c64xx_get_slave_ctrldata(spi);
+ cs = s3c64xx_get_cs_gpios(spi);
spi->controller_data = cs;
}
@@ -1077,7 +1091,7 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
sdd->sfr_start = mem_res->start;
sdd->cs_gpio = true;
if (pdev->dev.of_node) {
- if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL))
+ if (!of_find_property(pdev->dev.of_node, "cs-gpios", NULL))
sdd->cs_gpio = false;
ret = of_alias_get_id(pdev->dev.of_node, "spi");
--
1.7.9.5
--
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