TI omap2 mcspi allows the slave devices to configure the behavior of
the SPI master. This patch adds device tree support to the existing
options.
Signed-off-by: Matthias Brugger <matthias....@gmail.com>
---
Documentation/devicetree/bindings/spi/omap-spi.txt | 23 ++++++++++++
drivers/spi/spi-omap2-mcspi.c | 41 ++++++++++++++++++++++
2 files changed, 64 insertions(+)
diff --git a/Documentation/devicetree/bindings/spi/omap-spi.txt
b/Documentation/devicetree/bindings/spi/omap-spi.txt
index 938809c..fef16bf 100644
--- a/Documentation/devicetree/bindings/spi/omap-spi.txt
+++ b/Documentation/devicetree/bindings/spi/omap-spi.txt
@@ -10,8 +10,20 @@ Required properties:
input. The default is D0 as input and
D1 as output.
+SPI Controller specific data in SPI slave nodes:
+
+- The spi slave nodes can provide the following information which is used
+ by the spi controller.
+
+- ti,spi-cs-per-word: Set chipselect to be toggled on every word send.
+
+- ti,spi-turbo-mode: Set turbo mode for this device.
+
+
Example:
+- SoC Specific Portion:
+
mcspi1: mcspi@1 {
#address-cells = <1>;
#size-cells = <0>;
@@ -20,3 +32,14 @@ mcspi1: mcspi@1 {
ti,spi-num-cs = <4>;
};
+- Board Specific Portion:
+
+ spi-device@0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ controller-data {
+ ti,spi-cs-per-word = <1>;
+ ti,spi-turbo-mode = <0>;
+ };
+ };
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index 893c3d7..1ae5009 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -731,11 +731,47 @@ static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
return 15;
}
+static struct omap2_mcspi_device_config *omap2_mcspi_get_slave_ctrldata(
+ struct spi_device *spi)
+{
+ struct omap2_mcspi_device_config *cd;
+ struct device_node *slave_np, *data_np = NULL;
+
+ slave_np = spi->dev.of_node;
+ if (!slave_np) {
+ dev_err(&spi->dev, "device node 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");
+ return ERR_PTR(-EINVAL);
+ }
+
+ cd = kzalloc(sizeof(*cd), GFP_KERNEL);
+ if (!cd) {
+ dev_err(&spi->dev, "could not allocate memory for controller
data\n");
+ of_node_put(data_np);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ if (of_get_property(data_np, "ti,spi-cs-per-word", NULL))
+ cd->cs_per_word = 1;
+
+ if (of_get_property(data_np, "ti,spi-turbo-mode", NULL))
+ cd->turbo_mode = 1;
+
+ of_node_put(data_np);
+ return cd;
+}
+
/* called only when no transfer is active to this device */
static int omap2_mcspi_setup_transfer(struct spi_device *spi,
struct spi_transfer *t)
{
struct omap2_mcspi_cs *cs = spi->controller_state;
+ struct omap2_mcspi_device_config *cd = spi->controller_data;
struct omap2_mcspi *mcspi;
struct spi_master *spi_cntrl;
u32 l = 0, div = 0;
@@ -745,6 +781,11 @@ static int omap2_mcspi_setup_transfer(struct spi_device
*spi,
mcspi = spi_master_get_devdata(spi->master);
spi_cntrl = mcspi->master;
+ if (!cd && spi->dev.of_node) {
+ cd = omap2_mcspi_get_slave_ctrldata(spi);
+ spi->controller_data = cd;
+ }
+
if (t != NULL && t->bits_per_word)
word_len = t->bits_per_word;
--
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/
