/*
* 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/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 defined(CONFIG_INPUT_DM355EVM) || defined(CONFIG_INPUT_DM355EVM_MODULE)
#define msp_has_keyboard() true
#else
#define msp_has_keyboard() false
#endif
#if defined(CONFIG_LEDS_GPIO) || defined(CONFIG_LEDS_GPIO_MODULE)
#define msp_has_leds() true
#else
#define msp_has_leds() false
#endif
#if defined(CONFIG_RTC_DRV_DM355EVM) || defined(CONFIG_RTC_DRV_DM355EVM_MODULE)
#define msp_has_rtc() true
#else
#define msp_has_rtc() false
#endif
#if defined(CONFIG_VIDEO_TVP514X) || defined(CONFIG_VIDEO_TVP514X_MODULE)
#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 */
MSP_GPIO(1, SDMMC), MSP_GPIO(2, SDMMC), /* mmc0 WP, nCD */
MSP_GPIO(3, SDMMC), MSP_GPIO(4, 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) {
dev_dbg(&client->dev, "can't alloc dev\n");
status = -ENOMEM;
goto err;
}
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 err;
}
}
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 err;
}
}
status = platform_device_add(pdev);
err:
if (status < 0) {
platform_device_put(pdev);
dev_err(&client->dev, "can't add %s dev\n", name);
return ERR_PTR(status);
}
return &pdev->dev;
}
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.dev = &client->dev;
status = gpiochip_add(&dm355evm_msp_gpio);
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(gpio, config_inputs[i].label);
gpio_direction_input(gpio);
/* make it easy for userspace to see these */
gpio_export(gpio, false);
}
/* MMC/SD inputs -- right after the last config input */
if (client->dev.platform_data) {
void (*mmcsd_setup)(unsigned) = client->dev.platform_data;
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");
