diff options
Diffstat (limited to 'arch/arm/mach-omap1/i2c.c')
| -rw-r--r-- | arch/arm/mach-omap1/i2c.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/i2c.c b/arch/arm/mach-omap1/i2c.c new file mode 100644 index 000000000..22f945360 --- /dev/null +++ b/arch/arm/mach-omap1/i2c.c @@ -0,0 +1,167 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Helper module for board specific I2C bus registration + * + * Copyright (C) 2009 Nokia Corporation. + */ + +#include <linux/i2c.h> +#include <linux/platform_data/i2c-omap.h> + +#include "mux.h" +#include "soc.h" +#include "i2c.h" + +#define OMAP_I2C_SIZE 0x3f +#define OMAP1_I2C_BASE 0xfffb3800 + +static const char name[] = "omap_i2c"; + +static struct resource i2c_resources[2] = { +}; + +static struct platform_device omap_i2c_devices[1] = { +}; + +static void __init omap1_i2c_mux_pins(int bus_id) +{ + if (cpu_is_omap7xx()) { + omap_cfg_reg(I2C_7XX_SDA); + omap_cfg_reg(I2C_7XX_SCL); + } else { + omap_cfg_reg(I2C_SDA); + omap_cfg_reg(I2C_SCL); + } +} + +int __init omap_i2c_add_bus(struct omap_i2c_bus_platform_data *pdata, + int bus_id) +{ + struct platform_device *pdev; + struct resource *res; + + if (bus_id > 1) + return -EINVAL; + + omap1_i2c_mux_pins(bus_id); + + pdev = &omap_i2c_devices[bus_id - 1]; + pdev->id = bus_id; + pdev->name = name; + pdev->num_resources = ARRAY_SIZE(i2c_resources); + res = i2c_resources; + res[0].start = OMAP1_I2C_BASE; + res[0].end = res[0].start + OMAP_I2C_SIZE; + res[0].flags = IORESOURCE_MEM; + res[1].start = INT_I2C; + res[1].flags = IORESOURCE_IRQ; + pdev->resource = res; + + /* all OMAP1 have IP version 1 register set */ + pdata->rev = OMAP_I2C_IP_VERSION_1; + + /* all OMAP1 I2C are implemented like this */ + pdata->flags = OMAP_I2C_FLAG_NO_FIFO | + OMAP_I2C_FLAG_SIMPLE_CLOCK | + OMAP_I2C_FLAG_16BIT_DATA_REG | + OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK; + + /* how the cpu bus is wired up differs for 7xx only */ + + if (cpu_is_omap7xx()) + pdata->flags |= OMAP_I2C_FLAG_BUS_SHIFT_1; + else + pdata->flags |= OMAP_I2C_FLAG_BUS_SHIFT_2; + + pdev->dev.platform_data = pdata; + + return platform_device_register(pdev); +} + +#define OMAP_I2C_MAX_CONTROLLERS 4 +static struct omap_i2c_bus_platform_data i2c_pdata[OMAP_I2C_MAX_CONTROLLERS]; + +#define OMAP_I2C_CMDLINE_SETUP (BIT(31)) + +/** + * omap_i2c_bus_setup - Process command line options for the I2C bus speed + * @str: String of options + * + * This function allow to override the default I2C bus speed for given I2C + * bus with a command line option. + * + * Format: i2c_bus=bus_id,clkrate (in kHz) + * + * Returns 1 on success, 0 otherwise. + */ +static int __init omap_i2c_bus_setup(char *str) +{ + int ints[3]; + + get_options(str, 3, ints); + if (ints[0] < 2 || ints[1] < 1 || + ints[1] > OMAP_I2C_MAX_CONTROLLERS) + return 0; + i2c_pdata[ints[1] - 1].clkrate = ints[2]; + i2c_pdata[ints[1] - 1].clkrate |= OMAP_I2C_CMDLINE_SETUP; + + return 1; +} +__setup("i2c_bus=", omap_i2c_bus_setup); + +/* + * Register busses defined in command line but that are not registered with + * omap_register_i2c_bus from board initialization code. + */ +int __init omap_register_i2c_bus_cmdline(void) +{ + int i, err = 0; + + for (i = 0; i < ARRAY_SIZE(i2c_pdata); i++) + if (i2c_pdata[i].clkrate & OMAP_I2C_CMDLINE_SETUP) { + i2c_pdata[i].clkrate &= ~OMAP_I2C_CMDLINE_SETUP; + err = omap_i2c_add_bus(&i2c_pdata[i], i + 1); + if (err) + goto out; + } + +out: + return err; +} + +/** + * omap_register_i2c_bus - register I2C bus with device descriptors + * @bus_id: bus id counting from number 1 + * @clkrate: clock rate of the bus in kHz + * @info: pointer into I2C device descriptor table or NULL + * @len: number of descriptors in the table + * + * Returns 0 on success or an error code. + */ +int __init omap_register_i2c_bus(int bus_id, u32 clkrate, + struct i2c_board_info const *info, + unsigned len) +{ + int err; + + BUG_ON(bus_id < 1 || bus_id > OMAP_I2C_MAX_CONTROLLERS); + + if (info) { + err = i2c_register_board_info(bus_id, info, len); + if (err) + return err; + } + + if (!i2c_pdata[bus_id - 1].clkrate) + i2c_pdata[bus_id - 1].clkrate = clkrate; + + i2c_pdata[bus_id - 1].clkrate &= ~OMAP_I2C_CMDLINE_SETUP; + + return omap_i2c_add_bus(&i2c_pdata[bus_id - 1], bus_id); +} + +static int __init omap_i2c_cmdline(void) +{ + return omap_register_i2c_bus_cmdline(); +} +subsys_initcall(omap_i2c_cmdline); |