diff options
Diffstat (limited to 'package/kernel/spi-gpio-custom/src/spi-gpio-custom.c')
| -rw-r--r-- | package/kernel/spi-gpio-custom/src/spi-gpio-custom.c | 365 |
1 files changed, 0 insertions, 365 deletions
diff --git a/package/kernel/spi-gpio-custom/src/spi-gpio-custom.c b/package/kernel/spi-gpio-custom/src/spi-gpio-custom.c deleted file mode 100644 index 4c13b56d79..0000000000 --- a/package/kernel/spi-gpio-custom/src/spi-gpio-custom.c +++ /dev/null @@ -1,365 +0,0 @@ -/* - * Custom GPIO-based SPI driver - * - * Copyright (C) 2013 Marco Burato <zmaster.adsl@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. - * - * Based on i2c-gpio-custom by: - * Copyright (C) 2007-2008 Gabor Juhos <juhosg@openwrt.org> - * --------------------------------------------------------------------------- - * - * The behaviour of this driver can be altered by setting some parameters - * from the insmod command line. - * - * The following parameters are adjustable: - * - * bus0 These four arguments can be arrays of - * bus1 1-8 unsigned integers as follows: - * bus2 - * bus3 <id>,<sck>,<mosi>,<miso>,<mode1>,<maxfreq1>,<cs1>,... - * - * where: - * - * <id> ID to used as device_id for the corresponding bus (required) - * <sck> GPIO pin ID to be used for bus SCK (required) - * <mosi> GPIO pin ID to be used for bus MOSI (required*) - * <miso> GPIO pin ID to be used for bus MISO (required*) - * <modeX> Mode configuration for slave X in the bus (required) - * (see /include/linux/spi/spi.h) - * <maxfreqX> Maximum clock frequency in Hz for slave X in the bus (required) - * <csX> GPIO pin ID to be used for slave X CS (required**) - * - * Notes: - * * If a signal is not used (for example there is no MISO) you need - * to set the GPIO pin ID for that signal to an invalid value. - * ** If you only have 1 slave in the bus with no CS, you can omit the - * <cs1> param or set it to an invalid GPIO id to disable it. When - * you have 2 or more slaves, they must all have a valid CS. - * - * If this driver is built into the kernel, you can use the following kernel - * command line parameters, with the same values as the corresponding module - * parameters listed above: - * - * spi-gpio-custom.bus0 - * spi-gpio-custom.bus1 - * spi-gpio-custom.bus2 - * spi-gpio-custom.bus3 - */ - -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/init.h> -#include <linux/platform_device.h> - -#include <linux/gpio.h> -#include <linux/spi/spi.h> -#include <linux/spi/spi_gpio.h> - -#define DRV_NAME "spi-gpio-custom" -#define DRV_DESC "Custom GPIO-based SPI driver" -#define DRV_VERSION "0.1" - -#define PFX DRV_NAME ": " - -#define BUS_PARAM_ID 0 -#define BUS_PARAM_SCK 1 -#define BUS_PARAM_MOSI 2 -#define BUS_PARAM_MISO 3 -#define BUS_PARAM_MODE1 4 -#define BUS_PARAM_MAXFREQ1 5 -#define BUS_PARAM_CS1 6 - -#define BUS_SLAVE_COUNT_MAX 8 -#define BUS_PARAM_REQUIRED 6 -#define BUS_PARAM_PER_SLAVE 3 -#define BUS_PARAM_COUNT (4+BUS_PARAM_PER_SLAVE*BUS_SLAVE_COUNT_MAX) -#define BUS_COUNT_MAX 4 - -static unsigned int bus0[BUS_PARAM_COUNT] __initdata; -static unsigned int bus1[BUS_PARAM_COUNT] __initdata; -static unsigned int bus2[BUS_PARAM_COUNT] __initdata; -static unsigned int bus3[BUS_PARAM_COUNT] __initdata; - -static unsigned int bus_nump[BUS_COUNT_MAX] __initdata; - -#define BUS_PARM_DESC \ - " config -> id,sck,mosi,miso,mode1,maxfreq1[,cs1,mode2,maxfreq2,cs2,...]" - -module_param_array(bus0, uint, &bus_nump[0], 0); -MODULE_PARM_DESC(bus0, "bus0" BUS_PARM_DESC); -module_param_array(bus1, uint, &bus_nump[1], 0); -MODULE_PARM_DESC(bus1, "bus1" BUS_PARM_DESC); -module_param_array(bus2, uint, &bus_nump[2], 0); -MODULE_PARM_DESC(bus2, "bus2" BUS_PARM_DESC); -module_param_array(bus3, uint, &bus_nump[3], 0); -MODULE_PARM_DESC(bus3, "bus3" BUS_PARM_DESC); - -static struct platform_device *devices[BUS_COUNT_MAX]; -static unsigned int nr_devices; - -static void spi_gpio_custom_cleanup(void) -{ - int i; - - for (i = 0; i < nr_devices; i++) - if (devices[i]) - platform_device_unregister(devices[i]); -} - -static int __init spi_gpio_custom_get_slave_mode(unsigned int id, - unsigned int *params, - int slave_index) -{ - int param_index; - - param_index = BUS_PARAM_MODE1+slave_index*BUS_PARAM_PER_SLAVE; - if (param_index >= bus_nump[id]) - return -1; - - return params[param_index]; -} -static int __init spi_gpio_custom_get_slave_maxfreq(unsigned int id, - unsigned int *params, - int slave_index) -{ - int param_index; - - param_index = BUS_PARAM_MAXFREQ1+slave_index*BUS_PARAM_PER_SLAVE; - if (param_index >= bus_nump[id]) - return -1; - - return params[param_index]; -} -static int __init spi_gpio_custom_get_slave_cs(unsigned int id, - unsigned int *params, - int slave_index) -{ - int param_index; - - param_index = BUS_PARAM_CS1+slave_index*BUS_PARAM_PER_SLAVE; - if (param_index >= bus_nump[id]) - return -1; - if (!gpio_is_valid(params[param_index])) - return -1; - - return params[param_index]; -} - -static int __init spi_gpio_custom_check_params(unsigned int id, unsigned int *params) -{ - int i; - struct spi_master *master; - - if (bus_nump[id] < BUS_PARAM_REQUIRED) { - printk(KERN_ERR PFX "not enough values for parameter bus%d\n", - id); - return -EINVAL; - } - - if (bus_nump[id] > (1+BUS_PARAM_CS1)) { - /* more than 1 device: check CS GPIOs */ - for (i = 0; i < BUS_SLAVE_COUNT_MAX; i++) { - /* no more slaves? */ - if (spi_gpio_custom_get_slave_mode(id, params, i) < 0) - break; - - if (spi_gpio_custom_get_slave_cs(id, params, i) < 0) { - printk(KERN_ERR PFX "invalid/missing CS gpio for slave %d on bus %d\n", - i, params[BUS_PARAM_ID]); - return -EINVAL; - } - } - } - - if (!gpio_is_valid(params[BUS_PARAM_SCK])) { - printk(KERN_ERR PFX "invalid SCK gpio for bus %d\n", - params[BUS_PARAM_ID]); - return -EINVAL; - } - - master = spi_busnum_to_master(params[BUS_PARAM_ID]); - if (master) { - spi_master_put(master); - printk(KERN_ERR PFX "bus %d already exists\n", - params[BUS_PARAM_ID]); - return -EEXIST; - } - - return 0; -} - -static int __init spi_gpio_custom_add_one(unsigned int id, unsigned int *params) -{ - struct platform_device *pdev; - struct spi_gpio_platform_data pdata; - int i; - int num_cs; - int err; - struct spi_master *master; - struct spi_device *slave; - struct spi_board_info slave_info; - int mode, maxfreq, cs; - - - if (!bus_nump[id]) - return 0; - - err = spi_gpio_custom_check_params(id, params); - if (err) - goto err; - - /* Create BUS device node */ - - pdev = platform_device_alloc("spi_gpio", params[BUS_PARAM_ID]); - if (!pdev) { - err = -ENOMEM; - goto err; - } - - num_cs = 0; - for (i = 0; i < BUS_SLAVE_COUNT_MAX; i++) { - /* no more slaves? */ - if (spi_gpio_custom_get_slave_mode(id, params, i) < 0) - break; - - if (spi_gpio_custom_get_slave_cs(id, params, i) >= 0) - num_cs++; - } - if (num_cs == 0) { - /* - * Even if no CS is used, spi modules expect - * at least 1 (unused) - */ - num_cs = 1; - } - - pdata.sck = params[BUS_PARAM_SCK]; - pdata.mosi = gpio_is_valid(params[BUS_PARAM_MOSI]) - ? params[BUS_PARAM_MOSI] - : SPI_GPIO_NO_MOSI; - pdata.miso = gpio_is_valid(params[BUS_PARAM_MISO]) - ? params[BUS_PARAM_MISO] - : SPI_GPIO_NO_MISO; - pdata.num_chipselect = num_cs; - - err = platform_device_add_data(pdev, &pdata, sizeof(pdata)); - if (err) { - platform_device_put(pdev); - goto err; - } - - err = platform_device_add(pdev); - if (err) { - printk(KERN_ERR PFX "platform_device_add failed with return code %d\n", - err); - platform_device_put(pdev); - goto err; - } - - /* Register SLAVE devices */ - - for (i = 0; i < BUS_SLAVE_COUNT_MAX; i++) { - mode = spi_gpio_custom_get_slave_mode(id, params, i); - maxfreq = spi_gpio_custom_get_slave_maxfreq(id, params, i); - cs = spi_gpio_custom_get_slave_cs(id, params, i); - - /* no more slaves? */ - if (mode < 0) - break; - - memset(&slave_info, 0, sizeof(slave_info)); - strcpy(slave_info.modalias, "spidev"); - slave_info.controller_data = (void *)((cs >= 0) - ? cs - : SPI_GPIO_NO_CHIPSELECT); - slave_info.max_speed_hz = maxfreq; - slave_info.bus_num = params[BUS_PARAM_ID]; - slave_info.chip_select = i; - slave_info.mode = mode; - - master = spi_busnum_to_master(params[BUS_PARAM_ID]); - if (!master) { - printk(KERN_ERR PFX "unable to get master for bus %d\n", - params[BUS_PARAM_ID]); - err = -EINVAL; - goto err_unregister; - } - slave = spi_new_device(master, &slave_info); - spi_master_put(master); - if (!slave) { - printk(KERN_ERR PFX "unable to create slave %d for bus %d\n", - i, params[BUS_PARAM_ID]); - /* Will most likely fail due to unsupported mode bits */ - err = -EINVAL; - goto err_unregister; - } - } - - devices[nr_devices++] = pdev; - - return 0; - -err_unregister: - platform_device_unregister(pdev); -err: - return err; -} - -static int __init spi_gpio_custom_probe(void) -{ - int err; - - printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n"); - - err = spi_gpio_custom_add_one(0, bus0); - if (err) - goto err; - - err = spi_gpio_custom_add_one(1, bus1); - if (err) - goto err; - - err = spi_gpio_custom_add_one(2, bus2); - if (err) - goto err; - - err = spi_gpio_custom_add_one(3, bus3); - if (err) - goto err; - - if (!nr_devices) { - printk(KERN_ERR PFX "no bus parameter(s) specified\n"); - err = -ENODEV; - goto err; - } - - return 0; - -err: - spi_gpio_custom_cleanup(); - return err; -} - -#ifdef MODULE -static int __init spi_gpio_custom_init(void) -{ - return spi_gpio_custom_probe(); -} -module_init(spi_gpio_custom_init); - -static void __exit spi_gpio_custom_exit(void) -{ - spi_gpio_custom_cleanup(); -} -module_exit(spi_gpio_custom_exit); -#else -subsys_initcall(spi_gpio_custom_probe); -#endif /* MODULE*/ - -MODULE_LICENSE("GPL v2"); -MODULE_AUTHOR("Marco Burato <zmaster.adsl@gmail.com>"); -MODULE_DESCRIPTION(DRV_DESC); -MODULE_VERSION(DRV_VERSION); |