/* * dm355evm_msp.c - driver for MSP430 firmware on DM355EVM board * * Copyright (C) 2008 David Brownell * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ #include <linux/init.h> #include <linux/mutex.h> #include <linux/platform_device.h> #include <linux/clk.h> #include <linux/module.h> #include <linux/err.h> #include <linux/gpio.h> #include <linux/leds.h> #include <linux/i2c.h> #include <linux/i2c/dm355evm_msp.h> /* * The DM355 is a DaVinci chip with video support but no C64+ DSP. Its * EVM board has an MSP430 programmed with firmware for various board * support functions. This driver exposes some of them directly, and * supports other drivers (e.g. RTC, input) for more complex access. * * Because this firmware is entirely board-specific, this file embeds * knowledge that would be passed as platform_data in a generic driver. * * This driver was tested with firmware revision A4. */ #if IS_ENABLED(CONFIG_INPUT_DM355EVM) #define msp_has_keyboard() true #else #define msp_has_keyboard() false #endif #if IS_ENABLED(CONFIG_LEDS_GPIO) #define msp_has_leds() true #else #define msp_has_leds() false #endif #if IS_ENABLED(CONFIG_RTC_DRV_DM355EVM) #define msp_has_rtc() true #else #define msp_has_rtc() false #endif #if IS_ENABLED(CONFIG_VIDEO_TVP514X) #define msp_has_tvp() true #else #define msp_has_tvp() false #endif /*----------------------------------------------------------------------*/ /* REVISIT for paranoia's sake, retry reads/writes on error */ static struct i2c_client *msp430; /** * dm355evm_msp_write - Writes a register in dm355evm_msp * @value: the value to be written * @reg: register address * * Returns result of operation - 0 is success, else negative errno */ int dm355evm_msp_write(u8 value, u8 reg) { return i2c_smbus_write_byte_data(msp430, reg, value); } EXPORT_SYMBOL(dm355evm_msp_write); /** * dm355evm_msp_read - Reads a register from dm355evm_msp * @reg: register address * * Returns result of operation - value, or negative errno */ int dm355evm_msp_read(u8 reg) { return i2c_smbus_read_byte_data(msp430, reg); } EXPORT_SYMBOL(dm355evm_msp_read); /*----------------------------------------------------------------------*/ /* * Many of the msp430 pins are just used as fixed-direction GPIOs. * We could export a few more of them this way, if we wanted. */ #define MSP_GPIO(bit, reg) ((DM355EVM_MSP_ ## reg) << 3 | (bit)) static const u8 msp_gpios[] = { /* eight leds */ MSP_GPIO(0, LED), MSP_GPIO(1, LED), MSP_GPIO(2, LED), MSP_GPIO(3, LED), MSP_GPIO(4, LED), MSP_GPIO(5, LED), MSP_GPIO(6, LED), MSP_GPIO(7, LED), /* SW6 and the NTSC/nPAL jumper */ MSP_GPIO(0, SWITCH1), MSP_GPIO(1, SWITCH1), MSP_GPIO(2, SWITCH1), MSP_GPIO(3, SWITCH1), MSP_GPIO(4, SWITCH1), /* switches on MMC/SD sockets */ /* * Note: EVMDM355_ECP_VA4.pdf suggests that Bit 2 and 4 should be * checked for card detection. However on the EVM bit 1 and 3 gives * this status, for 0 and 1 instance respectively. The pdf also * suggests that Bit 1 and 3 should be checked for write protection. * However on the EVM bit 2 and 4 gives this status,for 0 and 1 * instance respectively. */ MSP_GPIO(2, SDMMC), MSP_GPIO(1, SDMMC), /* mmc0 WP, nCD */ MSP_GPIO(4, SDMMC), MSP_GPIO(3, SDMMC), /* mmc1 WP, nCD */ }; #define MSP_GPIO_REG(offset) (msp_gpios[(offset)] >> 3) #define MSP_GPIO_MASK(offset) BIT(msp_gpios[(offset)] & 0x07) static int msp_gpio_in(struct gpio_chip *chip, unsigned offset) { switch (MSP_GPIO_REG(offset)) { case DM355EVM_MSP_SWITCH1: case DM355EVM_MSP_SWITCH2: case DM355EVM_MSP_SDMMC: return 0; default: return -EINVAL; } } static u8 msp_led_cache; static int msp_gpio_get(struct gpio_chip *chip, unsigned offset) { int reg, status; reg = MSP_GPIO_REG(offset); status = dm355evm_msp_read(reg); if (status < 0) return status; if (reg == DM355EVM_MSP_LED) msp_led_cache = status; return !!(status & MSP_GPIO_MASK(offset)); } static int msp_gpio_out(struct gpio_chip *chip, unsigned offset, int value) { int mask, bits; /* NOTE: there are some other signals that could be * packaged as output GPIOs, but they aren't as useful * as the LEDs ... so for now we don't. */ if (MSP_GPIO_REG(offset) != DM355EVM_MSP_LED) return -EINVAL; mask = MSP_GPIO_MASK(offset); bits = msp_led_cache; bits &= ~mask; if (value) bits |= mask; msp_led_cache = bits; return dm355evm_msp_write(bits, DM355EVM_MSP_LED); } static void msp_gpio_set(struct gpio_chip *chip, unsigned offset, int value) { msp_gpio_out(chip, offset, value); } static struct gpio_chip dm355evm_msp_gpio = { .label = "dm355evm_msp", .owner = THIS_MODULE, .direction_input = msp_gpio_in, .get = msp_gpio_get, .direction_output = msp_gpio_out, .set = msp_gpio_set, .base = -EINVAL, /* dynamic assignment */ .ngpio = ARRAY_SIZE(msp_gpios), .can_sleep = true, }; /*----------------------------------------------------------------------*/ static struct device *add_child(struct i2c_client *client, const char *name, void *pdata, unsigned pdata_len, bool can_wakeup, int irq) { struct platform_device *pdev; int status; pdev = platform_device_alloc(name, -1); if (!pdev) return ERR_PTR(-ENOMEM); device_init_wakeup(&pdev->dev, can_wakeup); pdev->dev.parent = &client->dev; if (pdata) { status = platform_device_add_data(pdev, pdata, pdata_len); if (status < 0) { dev_dbg(&pdev->dev, "can't add platform_data\n"); goto put_device; } } if (irq) { struct resource r = { .start = irq, .flags = IORESOURCE_IRQ, }; status = platform_device_add_resources(pdev, &r, 1); if (status < 0) { dev_dbg(&pdev->dev, "can't add irq\n"); goto put_device; } } status = platform_device_add(pdev); if (status) goto put_device; return &pdev->dev; put_device: platform_device_put(pdev); dev_err(&client->dev, "failed to add device %s\n", name); return ERR_PTR(status); } static int add_children(struct i2c_client *client) { static const struct { int offset; char *label; } config_inputs[] = { /* 8 == right after the LEDs */ { 8 + 0, "sw6_1", }, { 8 + 1, "sw6_2", }, { 8 + 2, "sw6_3", }, { 8 + 3, "sw6_4", }, { 8 + 4, "NTSC/nPAL", }, }; struct device *child; int status; int i; /* GPIO-ish stuff */ dm355evm_msp_gpio.parent = &client->dev; status = gpiochip_add_data(&dm355evm_msp_gpio, NULL); if (status < 0) return status; /* LED output */ if (msp_has_leds()) { #define GPIO_LED(l) .name = l, .active_low = true static struct gpio_led evm_leds[] = { { GPIO_LED("dm355evm::ds14"), .default_trigger = "heartbeat", }, { GPIO_LED("dm355evm::ds15"), .default_trigger = "mmc0", }, { GPIO_LED("dm355evm::ds16"), /* could also be a CE-ATA drive */ .default_trigger = "mmc1", }, { GPIO_LED("dm355evm::ds17"), .default_trigger = "nand-disk", }, { GPIO_LED("dm355evm::ds18"), }, { GPIO_LED("dm355evm::ds19"), }, { GPIO_LED("dm355evm::ds20"), }, { GPIO_LED("dm355evm::ds21"), }, }; #undef GPIO_LED struct gpio_led_platform_data evm_led_data = { .num_leds = ARRAY_SIZE(evm_leds), .leds = evm_leds, }; for (i = 0; i < ARRAY_SIZE(evm_leds); i++) evm_leds[i].gpio = i + dm355evm_msp_gpio.base; /* NOTE: these are the only fully programmable LEDs * on the board, since GPIO-61/ds22 (and many signals * going to DC7) must be used for AEMIF address lines * unless the top 1 GB of NAND is unused... */ child = add_child(client, "leds-gpio", &evm_led_data, sizeof(evm_led_data), false, 0); if (IS_ERR(child)) return PTR_ERR(child); } /* configuration inputs */ for (i = 0; i < ARRAY_SIZE(config_inputs); i++) { int gpio = dm355evm_msp_gpio.base + config_inputs[i].offset; gpio_request_one(gpio, GPIOF_IN, config_inputs[i].label); /* make it easy for userspace to see these */ gpio_export(gpio, false); } /* MMC/SD inputs -- right after the last config input */ if (dev_get_platdata(&client->dev)) { void (*mmcsd_setup)(unsigned) = dev_get_platdata(&client->dev); mmcsd_setup(dm355evm_msp_gpio.base + 8 + 5); } /* RTC is a 32 bit counter, no alarm */ if (msp_has_rtc()) { child = add_child(client, "rtc-dm355evm", NULL, 0, false, 0); if (IS_ERR(child)) return PTR_ERR(child); } /* input from buttons and IR remote (uses the IRQ) */ if (msp_has_keyboard()) { child = add_child(client, "dm355evm_keys", NULL, 0, true, client->irq); if (IS_ERR(child)) return PTR_ERR(child); } return 0; } /*----------------------------------------------------------------------*/ static void dm355evm_command(unsigned command) { int status; status = dm355evm_msp_write(command, DM355EVM_MSP_COMMAND); if (status < 0) dev_err(&msp430->dev, "command %d failure %d\n", command, status); } static void dm355evm_power_off(void) { dm355evm_command(MSP_COMMAND_POWEROFF); } static int dm355evm_msp_remove(struct i2c_client *client) { pm_power_off = NULL; msp430 = NULL; return 0; } static int dm355evm_msp_probe(struct i2c_client *client, const struct i2c_device_id *id) { int status; const char *video = msp_has_tvp() ? "TVP5146" : "imager"; if (msp430) return -EBUSY; msp430 = client; /* display revision status; doubles as sanity check */ status = dm355evm_msp_read(DM355EVM_MSP_FIRMREV); if (status < 0) goto fail; dev_info(&client->dev, "firmware v.%02X, %s as video-in\n", status, video); /* mux video input: either tvp5146 or some external imager */ status = dm355evm_msp_write(msp_has_tvp() ? 0 : MSP_VIDEO_IMAGER, DM355EVM_MSP_VIDEO_IN); if (status < 0) dev_warn(&client->dev, "error %d muxing %s as video-in\n", status, video); /* init LED cache, and turn off the LEDs */ msp_led_cache = 0xff; dm355evm_msp_write(msp_led_cache, DM355EVM_MSP_LED); /* export capabilities we support */ status = add_children(client); if (status < 0) goto fail; /* PM hookup */ pm_power_off = dm355evm_power_off; return 0; fail: /* FIXME remove children ... */ dm355evm_msp_remove(client); return status; } static const struct i2c_device_id dm355evm_msp_ids[] = { { "dm355evm_msp", 0 }, { /* end of list */ }, }; MODULE_DEVICE_TABLE(i2c, dm355evm_msp_ids); static struct i2c_driver dm355evm_msp_driver = { .driver.name = "dm355evm_msp", .id_table = dm355evm_msp_ids, .probe = dm355evm_msp_probe, .remove = dm355evm_msp_remove, }; static int __init dm355evm_msp_init(void) { return i2c_add_driver(&dm355evm_msp_driver); } subsys_initcall(dm355evm_msp_init); static void __exit dm355evm_msp_exit(void) { i2c_del_driver(&dm355evm_msp_driver); } module_exit(dm355evm_msp_exit); MODULE_DESCRIPTION("Interface to MSP430 firmware on DM355EVM"); MODULE_LICENSE("GPL");