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authorJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>2012-11-23 13:44:39 +0100
committerGrant Likely <grant.likely@secretlab.ca>2012-12-17 17:11:32 +0000
commit850a5b670af6293fcb1852af57567d19150ff638 (patch)
tree929a247a47c6c4e58dcf77e5ca4b5490e46e0646
parentcb71941a682270dd5164d1332900694d19caa5e1 (diff)
downloadop-kernel-dev-850a5b670af6293fcb1852af57567d19150ff638.zip
op-kernel-dev-850a5b670af6293fcb1852af57567d19150ff638.tar.gz
spi/atmel: add DT support
Use the newly introduce cs-gpios dt support on atmel. We do not use the hardware cs as it's wired and has bugs and limitations. As the controller believes that only active-low devices/systems exists. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
-rw-r--r--Documentation/devicetree/bindings/spi/spi_atmel.txt26
-rw-r--r--drivers/spi/spi-atmel.c17
2 files changed, 42 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/spi/spi_atmel.txt b/Documentation/devicetree/bindings/spi/spi_atmel.txt
new file mode 100644
index 0000000..07e04cd
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi_atmel.txt
@@ -0,0 +1,26 @@
+Atmel SPI device
+
+Required properties:
+- compatible : should be "atmel,at91rm9200-spi".
+- reg: Address and length of the register set for the device
+- interrupts: Should contain spi interrupt
+- cs-gpios: chipselects
+
+Example:
+
+spi1: spi@fffcc000 {
+ compatible = "atmel,at91rm9200-spi";
+ reg = <0xfffcc000 0x4000>;
+ interrupts = <13 4 5>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ cs-gpios = <&pioB 3 0>;
+ status = "okay";
+
+ mmc-slot@0 {
+ compatible = "mmc-spi-slot";
+ reg = <0>;
+ gpios = <&pioC 4 0>; /* CD */
+ spi-max-frequency = <25000000>;
+ };
+};
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 75c0c4f..ab34497 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -20,6 +20,7 @@
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/platform_data/atmel.h>
+#include <linux/of.h>
#include <asm/io.h>
#include <asm/gpio.h>
@@ -768,6 +769,10 @@ static int atmel_spi_setup(struct spi_device *spi)
/* chipselect must have been muxed as GPIO (e.g. in board setup) */
npcs_pin = (unsigned int)spi->controller_data;
+
+ if (gpio_is_valid(spi->cs_gpio))
+ npcs_pin = spi->cs_gpio;
+
asd = spi->controller_state;
if (!asd) {
asd = kzalloc(sizeof(struct atmel_spi_device), GFP_KERNEL);
@@ -937,8 +942,9 @@ static int atmel_spi_probe(struct platform_device *pdev)
/* the spi->mode bits understood by this driver: */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+ master->dev.of_node = pdev->dev.of_node;
master->bus_num = pdev->id;
- master->num_chipselect = 4;
+ master->num_chipselect = master->dev.of_node ? 0 : 4;
master->setup = atmel_spi_setup;
master->transfer = atmel_spi_transfer;
master->cleanup = atmel_spi_cleanup;
@@ -1064,11 +1070,20 @@ static int atmel_spi_resume(struct platform_device *pdev)
#define atmel_spi_resume NULL
#endif
+#if defined(CONFIG_OF)
+static const struct of_device_id atmel_spi_dt_ids[] = {
+ { .compatible = "atmel,at91rm9200-spi" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids);
+#endif
static struct platform_driver atmel_spi_driver = {
.driver = {
.name = "atmel_spi",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(atmel_spi_dt_ids),
},
.suspend = atmel_spi_suspend,
.resume = atmel_spi_resume,
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