| /* |
| * linux/arch/arm/plat-omap/i2c.c |
| * |
| * Helper module for board specific I2C bus registration |
| * |
| * Copyright (C) 2007 Nokia Corporation. |
| * |
| * Contact: Jarkko Nikula <jhnikula@gmail.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * version 2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * 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/kernel.h> |
| #include <linux/platform_device.h> |
| #include <linux/i2c.h> |
| #include <linux/slab.h> |
| #include <linux/err.h> |
| #include <linux/clk.h> |
| |
| #include <mach/irqs.h> |
| #include <plat/i2c.h> |
| #include <plat/omap_device.h> |
| |
| #define OMAP_I2C_SIZE 0x3f |
| #define OMAP1_I2C_BASE 0xfffb3800 |
| #define OMAP1_INT_I2C (32 + 4) |
| |
| static const char name[] = "omap_i2c"; |
| |
| #define I2C_RESOURCE_BUILDER(base, irq) \ |
| { \ |
| .start = (base), \ |
| .end = (base) + OMAP_I2C_SIZE, \ |
| .flags = IORESOURCE_MEM, \ |
| }, \ |
| { \ |
| .start = (irq), \ |
| .flags = IORESOURCE_IRQ, \ |
| }, |
| |
| static struct resource i2c_resources[][2] = { |
| { I2C_RESOURCE_BUILDER(0, 0) }, |
| }; |
| |
| #define I2C_DEV_BUILDER(bus_id, res, data) \ |
| { \ |
| .id = (bus_id), \ |
| .name = name, \ |
| .num_resources = ARRAY_SIZE(res), \ |
| .resource = (res), \ |
| .dev = { \ |
| .platform_data = (data), \ |
| }, \ |
| } |
| |
| #define MAX_OMAP_I2C_HWMOD_NAME_LEN 16 |
| #define OMAP_I2C_MAX_CONTROLLERS 4 |
| static struct omap_i2c_bus_platform_data i2c_pdata[OMAP_I2C_MAX_CONTROLLERS]; |
| static struct platform_device omap_i2c_devices[] = { |
| I2C_DEV_BUILDER(1, i2c_resources[0], &i2c_pdata[0]), |
| }; |
| |
| #define OMAP_I2C_CMDLINE_SETUP (BIT(31)) |
| |
| static int __init omap_i2c_nr_ports(void) |
| { |
| int ports = 0; |
| |
| if (cpu_class_is_omap1()) |
| ports = 1; |
| else if (cpu_is_omap24xx()) |
| ports = 2; |
| else if (cpu_is_omap34xx()) |
| ports = 3; |
| else if (cpu_is_omap44xx()) |
| ports = 4; |
| |
| return ports; |
| } |
| |
| static inline int omap1_i2c_add_bus(int bus_id) |
| { |
| struct platform_device *pdev; |
| struct omap_i2c_bus_platform_data *pdata; |
| struct resource *res; |
| |
| omap1_i2c_mux_pins(bus_id); |
| |
| pdev = &omap_i2c_devices[bus_id - 1]; |
| res = pdev->resource; |
| res[0].start = OMAP1_I2C_BASE; |
| res[0].end = res[0].start + OMAP_I2C_SIZE; |
| res[1].start = OMAP1_INT_I2C; |
| pdata = &i2c_pdata[bus_id - 1]; |
| |
| /* 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; |
| |
| return platform_device_register(pdev); |
| } |
| |
| |
| #ifdef CONFIG_ARCH_OMAP2PLUS |
| static inline int omap2_i2c_add_bus(int bus_id) |
| { |
| int l; |
| struct omap_hwmod *oh; |
| struct platform_device *pdev; |
| char oh_name[MAX_OMAP_I2C_HWMOD_NAME_LEN]; |
| struct omap_i2c_bus_platform_data *pdata; |
| struct omap_i2c_dev_attr *dev_attr; |
| |
| omap2_i2c_mux_pins(bus_id); |
| |
| l = snprintf(oh_name, MAX_OMAP_I2C_HWMOD_NAME_LEN, "i2c%d", bus_id); |
| WARN(l >= MAX_OMAP_I2C_HWMOD_NAME_LEN, |
| "String buffer overflow in I2C%d device setup\n", bus_id); |
| oh = omap_hwmod_lookup(oh_name); |
| if (!oh) { |
| pr_err("Could not look up %s\n", oh_name); |
| return -EEXIST; |
| } |
| |
| pdata = &i2c_pdata[bus_id - 1]; |
| /* |
| * pass the hwmod class's CPU-specific knowledge of I2C IP revision in |
| * use, and functionality implementation flags, up to the OMAP I2C |
| * driver via platform data |
| */ |
| pdata->rev = oh->class->rev; |
| |
| dev_attr = (struct omap_i2c_dev_attr *)oh->dev_attr; |
| pdata->flags = dev_attr->flags; |
| |
| pdev = omap_device_build(name, bus_id, oh, pdata, |
| sizeof(struct omap_i2c_bus_platform_data), |
| NULL, 0, 0); |
| WARN(IS_ERR(pdev), "Could not build omap_device for %s\n", name); |
| |
| return PTR_RET(pdev); |
| } |
| #else |
| static inline int omap2_i2c_add_bus(int bus_id) |
| { |
| return 0; |
| } |
| #endif |
| |
| static int __init omap_i2c_add_bus(int bus_id) |
| { |
| if (cpu_class_is_omap1()) |
| return omap1_i2c_add_bus(bus_id); |
| else |
| return omap2_i2c_add_bus(bus_id); |
| } |
| |
| /** |
| * 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 ports; |
| int ints[3]; |
| |
| ports = omap_i2c_nr_ports(); |
| get_options(str, 3, ints); |
| if (ints[0] < 2 || ints[1] < 1 || ints[1] > ports) |
| 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. |
| */ |
| static 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(i + 1); |
| if (err) |
| goto out; |
| } |
| |
| out: |
| return err; |
| } |
| subsys_initcall(omap_register_i2c_bus_cmdline); |
| |
| /** |
| * 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_nr_ports()); |
| |
| 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(bus_id); |
| } |