[v2 PATCH 07/14] spi/atmel_spi: add DT support

Wenyou Yang wenyou.yang at atmel.com
Tue Dec 4 18:53:53 EST 2012


From: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>

The atmel_spi use only gpio for chip select.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
[wenyou.yang at atmel.com: Add driver data and compatible "atmel,at91sam9260-spi", "atmel,at91sam9x5-spi"]
Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
Cc: devicetree-discuss at lists.ozlabs.org
Cc: spi-devel-general at lists.sourceforge.net
Cc: grant.likely at secretlab.ca
Cc: rob.herring at calxeda.com
Cc: rob at landley.net
Cc: linux-doc at vger.kernel.org
Cc: richard.genoud at gmail.com
---
Hi, Richard,

This patches is based on the original patch from Jean-Christophe
	[PATCH] spi/atmel: add DT support
and merge the patch from Richard Genoud
	[PATCH] spi-atmel OF: complete documentation
ane wenyou yang add more compatible "atmel,at91sam9260-spi", "atmel,at91sam9x5-spi", 
	add driver data to get IP version and dma support.

Could you sign your signature in this patch?

Best Regards,
Wenyou Yang

 .../devicetree/bindings/spi/spi_atmel.txt          |   23 +++++
 drivers/spi/spi-atmel.c                            |  102 +++++++++++++++++---
 2 files changed, 113 insertions(+), 12 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/spi/spi_atmel.txt

diff --git a/Documentation/devicetree/bindings/spi/spi_atmel.txt b/Documentation/devicetree/bindings/spi/spi_atmel.txt
new file mode 100644
index 0000000..20cdc91
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi_atmel.txt
@@ -0,0 +1,23 @@
+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 macb interrupt
+- cs-gpio: Should contain the GPIOs used for chipselect.
+- dma-mask: device coherent dma mask.
+
+spi0: spi at f0000000 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	compatible = "atmel,at91rm9200-spi";
+	reg = <0xf0000000 0x100>;
+	interrupts = <13 4>;
+	cs-gpios = <&pioA 14 0
+		    &pioA 7 0 /* conflicts with TXD2 */
+		    &pioA 1 0 /* conflicts with RXD0 */
+		    &pioB 3 0 /* conflicts with ERXDV */
+		   >;
+	dma-mask = <0xffffffff>;
+	status = "disabled";
+};
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 37f54c3..e032e3d 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -19,6 +19,7 @@
 #include <linux/interrupt.h>
 #include <linux/spi/spi.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 #include <asm/io.h>
 #include <mach/board.h>
@@ -185,6 +186,10 @@
  * DMA transfers; transfer queue progress is driven by IRQs.  The clock
  * framework provides the base clock, subdivided for each spi_device.
  */
+struct atmel_spi_pdata {
+	u8			version;
+};
+
 struct atmel_spi {
 	spinlock_t		lock;
 	unsigned long		flags;
@@ -203,6 +208,7 @@ struct atmel_spi {
 	struct spi_transfer	*next_transfer;
 	unsigned long		next_remaining_bytes;
 	int			done_status;
+	struct atmel_spi_pdata	*pdata;
 
 	void			*buffer;
 	dma_addr_t		buffer_dma;
@@ -217,6 +223,51 @@ struct atmel_spi_device {
 #define BUFFER_SIZE		PAGE_SIZE
 #define INVALID_DMA_ADDRESS	0xffffffff
 
+static struct atmel_spi_pdata at91rm9200_config = {
+	.version = 1,
+};
+
+static struct atmel_spi_pdata at91sam9260_config = {
+	.version = 2,
+};
+
+static struct atmel_spi_pdata at91sam9x5_config = {
+	.version = 2,
+};
+
+static const struct platform_device_id atmel_spi_devtypes[] = {
+	{
+		.name = "spi-at91rm9200",
+		.driver_data = (unsigned long) &at91rm9200_config,
+	}, {
+		.name = "spi-at91sam9260",
+		.driver_data = (unsigned long) &at91sam9260_config,
+	}, {
+		.name = "spi-at91sam9x5",
+		.driver_data = (unsigned long) &at91sam9x5_config,
+	}, {
+		/* sentinel */
+	}
+};
+
+#if defined(CONFIG_OF)
+static const struct of_device_id atmel_spi_dt_ids[] = {
+	{
+		.compatible = "atmel,at91rm9200-spi",
+		.data = &at91rm9200_config,
+	} , {
+		.compatible = "atmel,at91sam9260-spi",
+		.data = &at91sam9260_config,
+	} , {
+		.compatible = "atmel,at91sam9x5-spi",
+		.data = &at91sam9x5_config,
+	}, {
+		/* sentinel */
+	}
+};
+MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids);
+#endif
+
 /*
  * Version 2 of the SPI controller has
  *  - CR.LASTXFER
@@ -229,11 +280,15 @@ struct atmel_spi_device {
  * register, but I haven't checked that it exists on all chips, and
  * this is cheaper anyway.
  */
-static bool atmel_spi_is_v2(void)
+static bool atmel_spi_is_v2(struct atmel_spi *as)
 {
-	return !cpu_is_at91rm9200();
+	if (as->pdata->version == 2)
+		return true;
+	else
+		return false;
 }
 
+
 /*
  * Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby
  * they assume that spi slave device state will not change on deselect, so
@@ -265,7 +320,7 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi)
 	unsigned active = spi->mode & SPI_CS_HIGH;
 	u32 mr;
 
-	if (atmel_spi_is_v2()) {
+	if (atmel_spi_is_v2(as)) {
 		/*
 		 * Always use CSR0. This ensures that the clock
 		 * switches to the correct idle polarity before we
@@ -320,7 +375,7 @@ static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi)
 			asd->npcs_pin, active ? " (low)" : "",
 			mr);
 
-	if (atmel_spi_is_v2() || spi->chip_select != 0)
+	if (atmel_spi_is_v2(as) || spi->chip_select != 0)
 		gpio_set_value(asd->npcs_pin, !active);
 }
 
@@ -710,7 +765,7 @@ static int atmel_spi_setup(struct spi_device *spi)
 	u32			scbr, csr;
 	unsigned int		bits = spi->bits_per_word;
 	unsigned long		bus_hz;
-	unsigned int		npcs_pin;
+	int			npcs_pin;
 	int			ret;
 
 	as = spi_master_get_devdata(spi->master);
@@ -733,7 +788,7 @@ static int atmel_spi_setup(struct spi_device *spi)
 	}
 
 	/* see notes above re chipselect */
-	if (!atmel_spi_is_v2()
+	if (!atmel_spi_is_v2(as)
 			&& spi->chip_select == 0
 			&& (spi->mode & SPI_CS_HIGH)) {
 		dev_dbg(&spi->dev, "setup: can't be active-high\n");
@@ -742,7 +797,7 @@ static int atmel_spi_setup(struct spi_device *spi)
 
 	/* v1 chips start out at half the peripheral bus speed. */
 	bus_hz = clk_get_rate(as->clk);
-	if (!atmel_spi_is_v2())
+	if (!atmel_spi_is_v2(as))
 		bus_hz /= 2;
 
 	if (spi->max_speed_hz) {
@@ -782,7 +837,9 @@ static int atmel_spi_setup(struct spi_device *spi)
 	csr |= SPI_BF(DLYBCT, 0);
 
 	/* 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))
+		spi->cs_gpio = (int)spi->controller_data;
+	npcs_pin = spi->cs_gpio;
 	asd = spi->controller_state;
 	if (!asd) {
 		asd = kzalloc(sizeof(struct atmel_spi_device), GFP_KERNEL);
@@ -812,7 +869,7 @@ static int atmel_spi_setup(struct spi_device *spi)
 		"setup: %lu Hz bpw %u mode 0x%x -> csr%d %08x\n",
 		bus_hz / scbr, bits, spi->mode, spi->chip_select, csr);
 
-	if (!atmel_spi_is_v2())
+	if (!atmel_spi_is_v2(as))
 		spi_writel(as, CSR0 + 4 * spi->chip_select, csr);
 
 	return 0;
@@ -899,7 +956,7 @@ static void atmel_spi_cleanup(struct spi_device *spi)
 {
 	struct atmel_spi	*as = spi_master_get_devdata(spi->master);
 	struct atmel_spi_device	*asd = spi->controller_state;
-	unsigned		gpio = (unsigned) spi->controller_data;
+	unsigned		gpio = spi->cs_gpio;
 
 	if (!asd)
 		return;
@@ -916,6 +973,21 @@ static void atmel_spi_cleanup(struct spi_device *spi)
 	kfree(asd);
 }
 
+static struct atmel_spi_pdata * __devinit atmel_spi_get_driver_data(
+					struct platform_device *pdev)
+{
+	if (pdev->dev.of_node) {
+		const struct of_device_id *match;
+		match = of_match_node(atmel_spi_dt_ids, pdev->dev.of_node);
+		if (!match)
+			return NULL;
+		return (struct atmel_spi_pdata *) match->data;
+	}
+
+	return (struct atmel_spi_pdata *)
+			platform_get_device_id(pdev)->driver_data;
+}
+
 /*-------------------------------------------------------------------------*/
 
 static int __devinit atmel_spi_probe(struct platform_device *pdev)
@@ -949,7 +1021,8 @@ static int __devinit atmel_spi_probe(struct platform_device *pdev)
 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 
 	master->bus_num = pdev->id;
-	master->num_chipselect = 4;
+	master->dev.of_node = pdev->dev.of_node;
+	master->num_chipselect = master->dev.of_node ? 0 : 4;
 	master->setup = atmel_spi_setup;
 	master->transfer = atmel_spi_transfer;
 	master->cleanup = atmel_spi_cleanup;
@@ -981,6 +1054,10 @@ static int __devinit atmel_spi_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_unmap_regs;
 
+	as->pdata = atmel_spi_get_driver_data(pdev);
+	if (!as->pdata)
+		goto out_unmap_regs;
+
 	/* Initialize the hardware */
 	clk_enable(clk);
 	spi_writel(as, CR, SPI_BIT(SWRST));
@@ -1078,12 +1155,13 @@ static int atmel_spi_resume(struct platform_device *pdev)
 #define	atmel_spi_resume	NULL
 #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),
 	},
+	.id_table	= atmel_spi_devtypes,
 	.suspend	= atmel_spi_suspend,
 	.resume		= atmel_spi_resume,
 	.probe		= atmel_spi_probe,
-- 
1.7.9.5



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