[PATCH 6/6] SMDK6410 SPI: Added spidev support as an example

[PATCH 6/6] SMDK6410 SPI: Added spidev support as an example

[Jassi Brar]

As an illustration of using the newly implemented SPI driver,
'spidev' master device has been enabled on SMDK6410.

Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
---
 arch/arm/mach-s3c6410/mach-smdk6410.c |   47 +++++++++++++++++++++++++++++++++
 1 files changed, 47 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-s3c6410/mach-smdk6410.c b/arch/arm/mach-s3c6410/mach-smdk6410.c
index ea51dbe..1230fa9 100644
--- a/arch/arm/mach-s3c6410/mach-smdk6410.c
+++ b/arch/arm/mach-s3c6410/mach-smdk6410.c
@@ -25,6 +25,7 @@
 #include <linux/gpio.h>
 #include <linux/delay.h>
 #include <linux/smsc911x.h>
+#include <linux/spi/spi.h>
 
 #ifdef CONFIG_SMDK6410_WM1190_EV1
 #include <linux/mfd/wm8350/core.h>
@@ -49,8 +50,10 @@
 #include <plat/regs-gpio.h>
 #include <plat/regs-sys.h>
 #include <plat/iic.h>
+#include <plat/spi.h>
 #include <plat/fb.h>
 #include <plat/gpio-cfg.h>
+#include <plat/gpio-bank-c.h>
 
 #include <plat/s3c6410.h>
 #include <plat/clock.h>
@@ -193,6 +196,7 @@ static struct platform_device *smdk6410_devices[] __initdata = {
 #ifdef CONFIG_SMDK6410_SD_CH1
 	&s3c_device_hsmmc1,
 #endif
+	&s3c64xx_device_spi0,
 	&s3c_device_i2c0,
 	&s3c_device_i2c1,
 	&s3c_device_fb,
@@ -351,6 +355,40 @@ static struct i2c_board_info i2c_devs1[] __initdata = {
 	{ I2C_BOARD_INFO("24c128", 0x57), },	/* Samsung S524AD0XD1 */
 };
 
+static void smdk6410_spidev_cs_set_level(int high)
+{
+	u32 val;
+
+	val = readl(S3C64XX_GPCDAT);
+
+	if (high)
+		val |= (1<<3);
+	else
+		val &= ~(1<<3);
+
+	writel(val, S3C64XX_GPCDAT);
+}
+
+#define SMDK6410_SPIDEV_CS 0
+
+static struct s3c64xx_spi_csinfo smdk6410_spi0_csi[] = {
+	[SMDK6410_SPIDEV_CS] = {
+		.set_level = smdk6410_spidev_cs_set_level,
+		.fb_delay = 0x3, /* 9ns feedback delay */
+	},
+};
+
+static struct spi_board_info smdk6410_spi_devices[] __initdata = {
+	{
+		.modalias	 = "spidev",
+		.mode		 = SPI_MODE_0,
+		.max_speed_hz    = 4000000,
+		.bus_num	 = 0,
+		.chip_select	 = 0,
+		.controller_data = &smdk6410_spi1_csi[SMDK6410_SPIDEV_CS],
+	},
+};
+
 static void __init smdk6410_map_io(void)
 {
 	u32 tmp;
@@ -385,6 +423,15 @@ static void __init smdk6410_machine_init(void)
 	i2c_register_board_info(0, i2c_devs0, ARRAY_SIZE(i2c_devs0));
 	i2c_register_board_info(1, i2c_devs1, ARRAY_SIZE(i2c_devs1));
 
+	/* SPI Controller-0 generates its clocks from PCLK and
+	 * emulates ARRAY_SIZE(smdk6410_spi0_csi) chipselects.
+	 */
+	s3c64xx_spi_set_info(BUSNUM(0), S3C64XX_SPI_SRCCLK_PCLK,
+					 ARRAY_SIZE(smdk6410_spi0_csi));
+
+	spi_register_board_info(smdk6410_spi_devices,
+					ARRAY_SIZE(smdk6410_spi_devices));
+
 	platform_add_devices(smdk6410_devices, ARRAY_SIZE(smdk6410_devices));
 }
 
-- 
1.6.2.5

Re: [PATCH 6/6] SMDK6410 SPI: Added spidev support as an example

[Mark Brown]

On Sat, Nov 21, 2009 at 11:52:28AM +0900, Jassi Brar wrote:

> +static void smdk6410_spidev_cs_set_level(int high)
> +{
> +	u32 val;
> +
> +	val = readl(S3C64XX_GPCDAT);
> +
> +	if (high)
> +		val |= (1<<3);
> +	else
> +		val &= ~(1<<3);
> +
> +	writel(val, S3C64XX_GPCDAT);
> +}

This should be using gpiolib, I suspect.

Re: [PATCH 6/6] SMDK6410 SPI: Added spidev support as an example

[jassi brar]

On Mon, Nov 23, 2009 at 10:23 PM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> On Sat, Nov 21, 2009 at 11:52:28AM +0900, Jassi Brar wrote:
>
>> +static void smdk6410_spidev_cs_set_level(int high)
>> +{
>> +     u32 val;
>> +
>> +     val = readl(S3C64XX_GPCDAT);
>> +
>> +     if (high)
>> +             val |= (1<<3);
>> +     else
>> +             val &= ~(1<<3);
>> +
>> +     writel(val, S3C64XX_GPCDAT);
>> +}
>
> This should be using gpiolib, I suspect.
yes, that wud be more appropriate. thanks.
Also, i anticipate objections to the utility of a spidev device when
smdk6410 doesn't even have convenient pins to tap the SPI signals.

Re: [PATCH 6/6] SMDK6410 SPI: Added spidev support as an example

[Mark Brown]

On Mon, Nov 23, 2009 at 10:41:40PM +0900, jassi brar wrote:

> Also, i anticipate objections to the utility of a spidev device when
> smdk6410 doesn't even have convenient pins to tap the SPI signals.

It does have the expansion ports under the LCD, though.