diff options
Diffstat (limited to 'target/linux/ar71xx/files/drivers/spi/spi-rb4xx-cpld.c')
| -rw-r--r-- | target/linux/ar71xx/files/drivers/spi/spi-rb4xx-cpld.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/target/linux/ar71xx/files/drivers/spi/spi-rb4xx-cpld.c b/target/linux/ar71xx/files/drivers/spi/spi-rb4xx-cpld.c new file mode 100644 index 000000000..4e8ce3105 --- /dev/null +++ b/target/linux/ar71xx/files/drivers/spi/spi-rb4xx-cpld.c @@ -0,0 +1,441 @@ +/* + * SPI driver for the CPLD chip on the Mikrotik RB4xx boards + * + * Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org> + * + * This file was based on the patches for Linux 2.6.27.39 published by + * MikroTik for their RouterBoard 4xx series devices. + * + * 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. + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/bitops.h> +#include <linux/spi/spi.h> +#include <linux/gpio.h> +#include <linux/slab.h> + +#include <asm/mach-ath79/rb4xx_cpld.h> + +#define DRV_NAME "spi-rb4xx-cpld" +#define DRV_DESC "RB4xx CPLD driver" +#define DRV_VERSION "0.1.0" + +#define CPLD_CMD_WRITE_NAND 0x08 /* send cmd, n x send data, send indle */ +#define CPLD_CMD_WRITE_CFG 0x09 /* send cmd, n x send cfg */ +#define CPLD_CMD_READ_NAND 0x0a /* send cmd, send idle, n x read data */ +#define CPLD_CMD_READ_FAST 0x0b /* send cmd, 4 x idle, n x read data */ +#define CPLD_CMD_LED5_ON 0x0c /* send cmd */ +#define CPLD_CMD_LED5_OFF 0x0d /* send cmd */ + +struct rb4xx_cpld { + struct spi_device *spi; + struct mutex lock; + struct gpio_chip chip; + unsigned int config; +}; + +static struct rb4xx_cpld *rb4xx_cpld; + +static inline struct rb4xx_cpld *gpio_to_cpld(struct gpio_chip *chip) +{ + return container_of(chip, struct rb4xx_cpld, chip); +} + +static int rb4xx_cpld_write_cmd(struct rb4xx_cpld *cpld, unsigned char cmd) +{ + struct spi_transfer t[1]; + struct spi_message m; + unsigned char tx_buf[1]; + int err; + + spi_message_init(&m); + memset(&t, 0, sizeof(t)); + + t[0].tx_buf = tx_buf; + t[0].len = sizeof(tx_buf); + spi_message_add_tail(&t[0], &m); + + tx_buf[0] = cmd; + + err = spi_sync(cpld->spi, &m); + return err; +} + +static int rb4xx_cpld_write_cfg(struct rb4xx_cpld *cpld, unsigned char config) +{ + struct spi_transfer t[1]; + struct spi_message m; + unsigned char cmd[2]; + int err; + + spi_message_init(&m); + memset(&t, 0, sizeof(t)); + + t[0].tx_buf = cmd; + t[0].len = sizeof(cmd); + spi_message_add_tail(&t[0], &m); + + cmd[0] = CPLD_CMD_WRITE_CFG; + cmd[1] = config; + + err = spi_sync(cpld->spi, &m); + return err; +} + +static int __rb4xx_cpld_change_cfg(struct rb4xx_cpld *cpld, unsigned mask, + unsigned value) +{ + unsigned int config; + int err; + + config = cpld->config & ~mask; + config |= value; + + if ((cpld->config ^ config) & 0xff) { + err = rb4xx_cpld_write_cfg(cpld, config); + if (err) + return err; + } + + if ((cpld->config ^ config) & CPLD_CFG_nLED5) { + err = rb4xx_cpld_write_cmd(cpld, (value) ? CPLD_CMD_LED5_ON : + CPLD_CMD_LED5_OFF); + if (err) + return err; + } + + cpld->config = config; + return 0; +} + +int rb4xx_cpld_change_cfg(unsigned mask, unsigned value) +{ + int ret; + + if (rb4xx_cpld == NULL) + return -ENODEV; + + mutex_lock(&rb4xx_cpld->lock); + ret = __rb4xx_cpld_change_cfg(rb4xx_cpld, mask, value); + mutex_unlock(&rb4xx_cpld->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(rb4xx_cpld_change_cfg); + +int rb4xx_cpld_read_from(unsigned addr, unsigned char *rx_buf, + const unsigned char *verify_buf, unsigned count) +{ + const unsigned char cmd[5] = { + CPLD_CMD_READ_FAST, + (addr >> 16) & 0xff, + (addr >> 8) & 0xff, + addr & 0xff, + 0 + }; + struct spi_transfer t[2] = { + { + .tx_buf = &cmd, + .len = 5, + }, + { + .tx_buf = verify_buf, + .rx_buf = rx_buf, + .len = count, + .verify = (verify_buf != NULL), + }, + }; + struct spi_message m; + + if (rb4xx_cpld == NULL) + return -ENODEV; + + spi_message_init(&m); + m.fast_read = 1; + spi_message_add_tail(&t[0], &m); + spi_message_add_tail(&t[1], &m); + return spi_sync(rb4xx_cpld->spi, &m); +} +EXPORT_SYMBOL_GPL(rb4xx_cpld_read_from); + +#if 0 +int rb4xx_cpld_read(unsigned char *buf, unsigned char *verify_buf, + unsigned count) +{ + struct spi_transfer t[2]; + struct spi_message m; + unsigned char cmd[2]; + + if (rb4xx_cpld == NULL) + return -ENODEV; + + spi_message_init(&m); + memset(&t, 0, sizeof(t)); + + /* send command */ + t[0].tx_buf = cmd; + t[0].len = sizeof(cmd); + spi_message_add_tail(&t[0], &m); + + cmd[0] = CPLD_CMD_READ_NAND; + cmd[1] = 0; + + /* read data */ + t[1].rx_buf = buf; + t[1].len = count; + spi_message_add_tail(&t[1], &m); + + return spi_sync(rb4xx_cpld->spi, &m); +} +#else +int rb4xx_cpld_read(unsigned char *rx_buf, const unsigned char *verify_buf, + unsigned count) +{ + static const unsigned char cmd[2] = { CPLD_CMD_READ_NAND, 0 }; + struct spi_transfer t[2] = { + { + .tx_buf = &cmd, + .len = 2, + }, { + .tx_buf = verify_buf, + .rx_buf = rx_buf, + .len = count, + .verify = (verify_buf != NULL), + }, + }; + struct spi_message m; + + if (rb4xx_cpld == NULL) + return -ENODEV; + + spi_message_init(&m); + spi_message_add_tail(&t[0], &m); + spi_message_add_tail(&t[1], &m); + return spi_sync(rb4xx_cpld->spi, &m); +} +#endif +EXPORT_SYMBOL_GPL(rb4xx_cpld_read); + +int rb4xx_cpld_write(const unsigned char *buf, unsigned count) +{ +#if 0 + struct spi_transfer t[3]; + struct spi_message m; + unsigned char cmd[1]; + + if (rb4xx_cpld == NULL) + return -ENODEV; + + memset(&t, 0, sizeof(t)); + spi_message_init(&m); + + /* send command */ + t[0].tx_buf = cmd; + t[0].len = sizeof(cmd); + spi_message_add_tail(&t[0], &m); + + cmd[0] = CPLD_CMD_WRITE_NAND; + + /* write data */ + t[1].tx_buf = buf; + t[1].len = count; + spi_message_add_tail(&t[1], &m); + + /* send idle */ + t[2].len = 1; + spi_message_add_tail(&t[2], &m); + + return spi_sync(rb4xx_cpld->spi, &m); +#else + static const unsigned char cmd = CPLD_CMD_WRITE_NAND; + struct spi_transfer t[3] = { + { + .tx_buf = &cmd, + .len = 1, + }, { + .tx_buf = buf, + .len = count, + .fast_write = 1, + }, { + .len = 1, + .fast_write = 1, + }, + }; + struct spi_message m; + + if (rb4xx_cpld == NULL) + return -ENODEV; + + spi_message_init(&m); + spi_message_add_tail(&t[0], &m); + spi_message_add_tail(&t[1], &m); + spi_message_add_tail(&t[2], &m); + return spi_sync(rb4xx_cpld->spi, &m); +#endif +} +EXPORT_SYMBOL_GPL(rb4xx_cpld_write); + +static int rb4xx_cpld_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct rb4xx_cpld *cpld = gpio_to_cpld(chip); + int ret; + + mutex_lock(&cpld->lock); + ret = (cpld->config >> offset) & 1; + mutex_unlock(&cpld->lock); + + return ret; +} + +static void rb4xx_cpld_gpio_set(struct gpio_chip *chip, unsigned offset, + int value) +{ + struct rb4xx_cpld *cpld = gpio_to_cpld(chip); + + mutex_lock(&cpld->lock); + __rb4xx_cpld_change_cfg(cpld, (1 << offset), !!value << offset); + mutex_unlock(&cpld->lock); +} + +static int rb4xx_cpld_gpio_direction_input(struct gpio_chip *chip, + unsigned offset) +{ + return -EOPNOTSUPP; +} + +static int rb4xx_cpld_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, + int value) +{ + struct rb4xx_cpld *cpld = gpio_to_cpld(chip); + int ret; + + mutex_lock(&cpld->lock); + ret = __rb4xx_cpld_change_cfg(cpld, (1 << offset), !!value << offset); + mutex_unlock(&cpld->lock); + + return ret; +} + +static int rb4xx_cpld_gpio_init(struct rb4xx_cpld *cpld, unsigned int base) +{ + int err; + + /* init config */ + cpld->config = CPLD_CFG_nLED1 | CPLD_CFG_nLED2 | CPLD_CFG_nLED3 | + CPLD_CFG_nLED4 | CPLD_CFG_nCE; + rb4xx_cpld_write_cfg(cpld, cpld->config); + + /* setup GPIO chip */ + cpld->chip.label = DRV_NAME; + + cpld->chip.get = rb4xx_cpld_gpio_get; + cpld->chip.set = rb4xx_cpld_gpio_set; + cpld->chip.direction_input = rb4xx_cpld_gpio_direction_input; + cpld->chip.direction_output = rb4xx_cpld_gpio_direction_output; + + cpld->chip.base = base; + cpld->chip.ngpio = CPLD_NUM_GPIOS; + cpld->chip.can_sleep = 1; + cpld->chip.dev = &cpld->spi->dev; + cpld->chip.owner = THIS_MODULE; + + err = gpiochip_add(&cpld->chip); + if (err) + dev_err(&cpld->spi->dev, "adding GPIO chip failed, err=%d\n", + err); + + return err; +} + +static int __devinit rb4xx_cpld_probe(struct spi_device *spi) +{ + struct rb4xx_cpld *cpld; + struct rb4xx_cpld_platform_data *pdata; + int err; + + pdata = spi->dev.platform_data; + if (!pdata) { + dev_dbg(&spi->dev, "no platform data\n"); + return -EINVAL; + } + + cpld = kzalloc(sizeof(*cpld), GFP_KERNEL); + if (!cpld) { + dev_err(&spi->dev, "no memory for private data\n"); + return -ENOMEM; + } + + mutex_init(&cpld->lock); + cpld->spi = spi_dev_get(spi); + dev_set_drvdata(&spi->dev, cpld); + + spi->mode = SPI_MODE_0; + spi->bits_per_word = 8; + err = spi_setup(spi); + if (err) { + dev_err(&spi->dev, "spi_setup failed, err=%d\n", err); + goto err_drvdata; + } + + err = rb4xx_cpld_gpio_init(cpld, pdata->gpio_base); + if (err) + goto err_drvdata; + + rb4xx_cpld = cpld; + + return 0; + +err_drvdata: + dev_set_drvdata(&spi->dev, NULL); + kfree(cpld); + + return err; +} + +static int __devexit rb4xx_cpld_remove(struct spi_device *spi) +{ + struct rb4xx_cpld *cpld; + + rb4xx_cpld = NULL; + cpld = dev_get_drvdata(&spi->dev); + dev_set_drvdata(&spi->dev, NULL); + kfree(cpld); + + return 0; +} + +static struct spi_driver rb4xx_cpld_driver = { + .driver = { + .name = DRV_NAME, + .bus = &spi_bus_type, + .owner = THIS_MODULE, + }, + .probe = rb4xx_cpld_probe, + .remove = __devexit_p(rb4xx_cpld_remove), +}; + +static int __init rb4xx_cpld_init(void) +{ + return spi_register_driver(&rb4xx_cpld_driver); +} +module_init(rb4xx_cpld_init); + +static void __exit rb4xx_cpld_exit(void) +{ + spi_unregister_driver(&rb4xx_cpld_driver); +} +module_exit(rb4xx_cpld_exit); + +MODULE_DESCRIPTION(DRV_DESC); +MODULE_VERSION(DRV_VERSION); +MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>"); +MODULE_LICENSE("GPL v2"); |