diff options
Diffstat (limited to 'arch/arm/mach-shmobile')
-rw-r--r-- | arch/arm/mach-shmobile/setup-r8a7740.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/arch/arm/mach-shmobile/setup-r8a7740.c b/arch/arm/mach-shmobile/setup-r8a7740.c index 55485187f0c7..e16860f04934 100644 --- a/arch/arm/mach-shmobile/setup-r8a7740.c +++ b/arch/arm/mach-shmobile/setup-r8a7740.c @@ -17,8 +17,10 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ +#include <linux/delay.h> #include <linux/kernel.h> #include <linux/init.h> +#include <linux/io.h> #include <linux/platform_device.h> #include <linux/serial_sci.h> #include <linux/sh_timer.h> @@ -233,10 +235,114 @@ static struct platform_device *r8a7740_early_devices[] __initdata = { &cmt10_device, }; +/* I2C */ +static struct resource i2c0_resources[] = { + [0] = { + .name = "IIC0", + .start = 0xfff20000, + .end = 0xfff20425 - 1, + .flags = IORESOURCE_MEM, + }, + [1] = { + .start = gic_spi(201), + .end = gic_spi(204), + .flags = IORESOURCE_IRQ, + }, +}; + +static struct resource i2c1_resources[] = { + [0] = { + .name = "IIC1", + .start = 0xe6c20000, + .end = 0xe6c20425 - 1, + .flags = IORESOURCE_MEM, + }, + [1] = { + .start = gic_spi(70), + .end = gic_spi(73), + .flags = IORESOURCE_IRQ, + }, +}; + +static struct platform_device i2c0_device = { + .name = "i2c-sh_mobile", + .id = 0, + .resource = i2c0_resources, + .num_resources = ARRAY_SIZE(i2c0_resources), +}; + +static struct platform_device i2c1_device = { + .name = "i2c-sh_mobile", + .id = 1, + .resource = i2c1_resources, + .num_resources = ARRAY_SIZE(i2c1_resources), +}; + +static struct platform_device *r8a7740_late_devices[] __initdata = { + &i2c0_device, + &i2c1_device, +}; + +#define ICCR 0x0004 +#define ICSTART 0x0070 + +#define i2c_read(reg, offset) ioread8(reg + offset) +#define i2c_write(reg, offset, data) iowrite8(data, reg + offset) + +/* + * r8a7740 chip has lasting errata on I2C I/O pad reset. + * this is work-around for it. + */ +static void r8a7740_i2c_workaround(struct platform_device *pdev) +{ + struct resource *res; + void __iomem *reg; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (unlikely(!res)) { + pr_err("r8a7740 i2c workaround fail (cannot find resource)\n"); + return; + } + + reg = ioremap(res->start, resource_size(res)); + if (unlikely(!reg)) { + pr_err("r8a7740 i2c workaround fail (cannot map IO)\n"); + return; + } + + i2c_write(reg, ICCR, i2c_read(reg, ICCR) | 0x80); + i2c_read(reg, ICCR); /* dummy read */ + + i2c_write(reg, ICSTART, i2c_read(reg, ICSTART) | 0x10); + i2c_read(reg, ICSTART); /* dummy read */ + + mdelay(100); + + i2c_write(reg, ICCR, 0x01); + i2c_read(reg, ICCR); + i2c_write(reg, ICSTART, 0x00); + i2c_read(reg, ICSTART); + + i2c_write(reg, ICCR, 0x10); + mdelay(100); + i2c_write(reg, ICCR, 0x00); + mdelay(100); + i2c_write(reg, ICCR, 0x10); + mdelay(100); + + iounmap(reg); +} + void __init r8a7740_add_standard_devices(void) { + /* I2C work-around */ + r8a7740_i2c_workaround(&i2c0_device); + r8a7740_i2c_workaround(&i2c1_device); + platform_add_devices(r8a7740_early_devices, ARRAY_SIZE(r8a7740_early_devices)); + platform_add_devices(r8a7740_late_devices, + ARRAY_SIZE(r8a7740_late_devices)); } void __init r8a7740_add_early_devices(void) |