diff options
Diffstat (limited to 'drivers/mfd/lochnagar-i2c.c')
-rw-r--r-- | drivers/mfd/lochnagar-i2c.c | 398 |
1 files changed, 398 insertions, 0 deletions
diff --git a/drivers/mfd/lochnagar-i2c.c b/drivers/mfd/lochnagar-i2c.c new file mode 100644 index 0000000000..59092f839d --- /dev/null +++ b/drivers/mfd/lochnagar-i2c.c @@ -0,0 +1,398 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Lochnagar I2C bus interface + * + * Copyright (c) 2012-2018 Cirrus Logic, Inc. and + * Cirrus Logic International Semiconductor Ltd. + * + * Author: Charles Keepax <ckeepax@opensource.cirrus.com> + */ + +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/lockdep.h> +#include <linux/mfd/core.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/regmap.h> + +#include <linux/mfd/lochnagar.h> +#include <linux/mfd/lochnagar1_regs.h> +#include <linux/mfd/lochnagar2_regs.h> + +#define LOCHNAGAR_BOOT_RETRIES 10 +#define LOCHNAGAR_BOOT_DELAY_MS 350 + +#define LOCHNAGAR_CONFIG_POLL_US 10000 + +static bool lochnagar1_readable_register(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LOCHNAGAR_SOFTWARE_RESET: + case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2: + case LOCHNAGAR1_CDC_AIF1_SEL...LOCHNAGAR1_CDC_AIF3_SEL: + case LOCHNAGAR1_CDC_MCLK1_SEL...LOCHNAGAR1_CDC_MCLK2_SEL: + case LOCHNAGAR1_CDC_AIF_CTRL1...LOCHNAGAR1_CDC_AIF_CTRL2: + case LOCHNAGAR1_EXT_AIF_CTRL: + case LOCHNAGAR1_DSP_AIF1_SEL...LOCHNAGAR1_DSP_AIF2_SEL: + case LOCHNAGAR1_DSP_CLKIN_SEL: + case LOCHNAGAR1_DSP_AIF: + case LOCHNAGAR1_GF_AIF1...LOCHNAGAR1_GF_AIF2: + case LOCHNAGAR1_PSIA_AIF: + case LOCHNAGAR1_PSIA1_SEL...LOCHNAGAR1_PSIA2_SEL: + case LOCHNAGAR1_SPDIF_AIF_SEL: + case LOCHNAGAR1_GF_AIF3_SEL...LOCHNAGAR1_GF_AIF4_SEL: + case LOCHNAGAR1_GF_CLKOUT1_SEL: + case LOCHNAGAR1_GF_AIF1_SEL...LOCHNAGAR1_GF_AIF2_SEL: + case LOCHNAGAR1_GF_GPIO2...LOCHNAGAR1_GF_GPIO7: + case LOCHNAGAR1_RST: + case LOCHNAGAR1_LED1...LOCHNAGAR1_LED2: + case LOCHNAGAR1_I2C_CTRL: + return true; + default: + return false; + } +} + +static const struct regmap_config lochnagar1_i2c_regmap = { + .reg_bits = 8, + .val_bits = 8, + .reg_format_endian = REGMAP_ENDIAN_BIG, + .val_format_endian = REGMAP_ENDIAN_BIG, + + .max_register = 0x50, + .readable_reg = lochnagar1_readable_register, + + .use_single_read = true, + .use_single_write = true, + + .cache_type = REGCACHE_RBTREE, +}; + +static const struct reg_sequence lochnagar1_patch[] = { + { 0x40, 0x0083 }, + { 0x47, 0x0018 }, + { 0x50, 0x0000 }, +}; + +static bool lochnagar2_readable_register(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LOCHNAGAR_SOFTWARE_RESET: + case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2: + case LOCHNAGAR2_CDC_AIF1_CTRL...LOCHNAGAR2_CDC_AIF3_CTRL: + case LOCHNAGAR2_DSP_AIF1_CTRL...LOCHNAGAR2_DSP_AIF2_CTRL: + case LOCHNAGAR2_PSIA1_CTRL...LOCHNAGAR2_PSIA2_CTRL: + case LOCHNAGAR2_GF_AIF3_CTRL...LOCHNAGAR2_GF_AIF4_CTRL: + case LOCHNAGAR2_GF_AIF1_CTRL...LOCHNAGAR2_GF_AIF2_CTRL: + case LOCHNAGAR2_SPDIF_AIF_CTRL: + case LOCHNAGAR2_USB_AIF1_CTRL...LOCHNAGAR2_USB_AIF2_CTRL: + case LOCHNAGAR2_ADAT_AIF_CTRL: + case LOCHNAGAR2_CDC_MCLK1_CTRL...LOCHNAGAR2_CDC_MCLK2_CTRL: + case LOCHNAGAR2_DSP_CLKIN_CTRL: + case LOCHNAGAR2_PSIA1_MCLK_CTRL...LOCHNAGAR2_PSIA2_MCLK_CTRL: + case LOCHNAGAR2_SPDIF_MCLK_CTRL: + case LOCHNAGAR2_GF_CLKOUT1_CTRL...LOCHNAGAR2_GF_CLKOUT2_CTRL: + case LOCHNAGAR2_ADAT_MCLK_CTRL: + case LOCHNAGAR2_SOUNDCARD_MCLK_CTRL: + case LOCHNAGAR2_GPIO_FPGA_GPIO1...LOCHNAGAR2_GPIO_FPGA_GPIO6: + case LOCHNAGAR2_GPIO_CDC_GPIO1...LOCHNAGAR2_GPIO_CDC_GPIO8: + case LOCHNAGAR2_GPIO_DSP_GPIO1...LOCHNAGAR2_GPIO_DSP_GPIO6: + case LOCHNAGAR2_GPIO_GF_GPIO2...LOCHNAGAR2_GPIO_GF_GPIO7: + case LOCHNAGAR2_GPIO_CDC_AIF1_BCLK...LOCHNAGAR2_GPIO_CDC_AIF3_TXDAT: + case LOCHNAGAR2_GPIO_DSP_AIF1_BCLK...LOCHNAGAR2_GPIO_DSP_AIF2_TXDAT: + case LOCHNAGAR2_GPIO_PSIA1_BCLK...LOCHNAGAR2_GPIO_PSIA2_TXDAT: + case LOCHNAGAR2_GPIO_GF_AIF3_BCLK...LOCHNAGAR2_GPIO_GF_AIF4_TXDAT: + case LOCHNAGAR2_GPIO_GF_AIF1_BCLK...LOCHNAGAR2_GPIO_GF_AIF2_TXDAT: + case LOCHNAGAR2_GPIO_DSP_UART1_RX...LOCHNAGAR2_GPIO_DSP_UART2_TX: + case LOCHNAGAR2_GPIO_GF_UART2_RX...LOCHNAGAR2_GPIO_GF_UART2_TX: + case LOCHNAGAR2_GPIO_USB_UART_RX: + case LOCHNAGAR2_GPIO_CDC_PDMCLK1...LOCHNAGAR2_GPIO_CDC_PDMDAT2: + case LOCHNAGAR2_GPIO_CDC_DMICCLK1...LOCHNAGAR2_GPIO_CDC_DMICDAT4: + case LOCHNAGAR2_GPIO_DSP_DMICCLK1...LOCHNAGAR2_GPIO_DSP_DMICDAT2: + case LOCHNAGAR2_GPIO_I2C2_SCL...LOCHNAGAR2_GPIO_I2C4_SDA: + case LOCHNAGAR2_GPIO_DSP_STANDBY: + case LOCHNAGAR2_GPIO_CDC_MCLK1...LOCHNAGAR2_GPIO_CDC_MCLK2: + case LOCHNAGAR2_GPIO_DSP_CLKIN: + case LOCHNAGAR2_GPIO_PSIA1_MCLK...LOCHNAGAR2_GPIO_PSIA2_MCLK: + case LOCHNAGAR2_GPIO_GF_GPIO1...LOCHNAGAR2_GPIO_GF_GPIO5: + case LOCHNAGAR2_GPIO_DSP_GPIO20: + case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16: + case LOCHNAGAR2_MINICARD_RESETS: + case LOCHNAGAR2_ANALOGUE_PATH_CTRL1...LOCHNAGAR2_ANALOGUE_PATH_CTRL2: + case LOCHNAGAR2_COMMS_CTRL4: + case LOCHNAGAR2_SPDIF_CTRL: + case LOCHNAGAR2_IMON_CTRL1...LOCHNAGAR2_IMON_CTRL4: + case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2: + case LOCHNAGAR2_POWER_CTRL: + case LOCHNAGAR2_MICVDD_CTRL1: + case LOCHNAGAR2_MICVDD_CTRL2: + case LOCHNAGAR2_VDDCORE_CDC_CTRL1: + case LOCHNAGAR2_VDDCORE_CDC_CTRL2: + case LOCHNAGAR2_SOUNDCARD_AIF_CTRL: + return true; + default: + return false; + } +} + +static bool lochnagar2_volatile_register(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16: + case LOCHNAGAR2_ANALOGUE_PATH_CTRL1: + case LOCHNAGAR2_IMON_CTRL3...LOCHNAGAR2_IMON_CTRL4: + case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2: + return true; + default: + return false; + } +} + +static const struct regmap_config lochnagar2_i2c_regmap = { + .reg_bits = 16, + .val_bits = 16, + .reg_format_endian = REGMAP_ENDIAN_BIG, + .val_format_endian = REGMAP_ENDIAN_BIG, + + .max_register = 0x1F1F, + .readable_reg = lochnagar2_readable_register, + .volatile_reg = lochnagar2_volatile_register, + + .cache_type = REGCACHE_RBTREE, +}; + +static const struct reg_sequence lochnagar2_patch[] = { + { 0x00EE, 0x0000 }, +}; + +struct lochnagar_config { + int id; + const char * const name; + enum lochnagar_type type; + const struct regmap_config *regmap; + const struct reg_sequence *patch; + int npatch; +}; + +static struct lochnagar_config lochnagar_configs[] = { + { + .id = 0x50, + .name = "lochnagar1", + .type = LOCHNAGAR1, + .regmap = &lochnagar1_i2c_regmap, + .patch = lochnagar1_patch, + .npatch = ARRAY_SIZE(lochnagar1_patch), + }, + { + .id = 0xCB58, + .name = "lochnagar2", + .type = LOCHNAGAR2, + .regmap = &lochnagar2_i2c_regmap, + .patch = lochnagar2_patch, + .npatch = ARRAY_SIZE(lochnagar2_patch), + }, +}; + +static const struct of_device_id lochnagar_of_match[] = { + { .compatible = "cirrus,lochnagar1", .data = &lochnagar_configs[0] }, + { .compatible = "cirrus,lochnagar2", .data = &lochnagar_configs[1] }, + {}, +}; + +static int lochnagar_wait_for_boot(struct regmap *regmap, unsigned int *id) +{ + int i, ret; + + for (i = 0; i < LOCHNAGAR_BOOT_RETRIES; ++i) { + msleep(LOCHNAGAR_BOOT_DELAY_MS); + + /* The reset register will return the device ID when read */ + ret = regmap_read(regmap, LOCHNAGAR_SOFTWARE_RESET, id); + if (!ret) + return ret; + } + + return -ETIMEDOUT; +} + +/** + * lochnagar_update_config - Synchronise the boards analogue configuration to + * the hardware. + * + * @lochnagar: A pointer to the primary core data structure. + * + * Return: Zero on success or an appropriate negative error code on failure. + */ +int lochnagar_update_config(struct lochnagar *lochnagar) +{ + struct regmap *regmap = lochnagar->regmap; + unsigned int done = LOCHNAGAR2_ANALOGUE_PATH_UPDATE_STS_MASK; + int timeout_ms = LOCHNAGAR_BOOT_DELAY_MS * LOCHNAGAR_BOOT_RETRIES; + unsigned int val = 0; + int ret; + + lockdep_assert_held(&lochnagar->analogue_config_lock); + + if (lochnagar->type != LOCHNAGAR2) + return 0; + + /* + * Toggle the ANALOGUE_PATH_UPDATE bit and wait for the device to + * acknowledge that any outstanding changes to the analogue + * configuration have been applied. + */ + ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1, 0); + if (ret < 0) + return ret; + + ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1, + LOCHNAGAR2_ANALOGUE_PATH_UPDATE_MASK); + if (ret < 0) + return ret; + + ret = regmap_read_poll_timeout(regmap, + LOCHNAGAR2_ANALOGUE_PATH_CTRL1, val, + (val & done), LOCHNAGAR_CONFIG_POLL_US, + timeout_ms * 1000); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL_GPL(lochnagar_update_config); + +static int lochnagar_i2c_probe(struct i2c_client *i2c) +{ + struct device *dev = &i2c->dev; + const struct lochnagar_config *config = NULL; + const struct of_device_id *of_id; + struct lochnagar *lochnagar; + struct gpio_desc *reset, *present; + unsigned int val; + unsigned int firmwareid; + unsigned int devid, rev; + int ret; + + lochnagar = devm_kzalloc(dev, sizeof(*lochnagar), GFP_KERNEL); + if (!lochnagar) + return -ENOMEM; + + of_id = of_match_device(lochnagar_of_match, dev); + if (!of_id) + return -EINVAL; + + config = of_id->data; + + lochnagar->dev = dev; + mutex_init(&lochnagar->analogue_config_lock); + + dev_set_drvdata(dev, lochnagar); + + reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(reset)) { + ret = PTR_ERR(reset); + dev_err(dev, "Failed to get reset GPIO: %d\n", ret); + return ret; + } + + present = devm_gpiod_get_optional(dev, "present", GPIOD_OUT_HIGH); + if (IS_ERR(present)) { + ret = PTR_ERR(present); + dev_err(dev, "Failed to get present GPIO: %d\n", ret); + return ret; + } + + /* Leave the Lochnagar in reset for a reasonable amount of time */ + msleep(20); + + /* Bring Lochnagar out of reset */ + gpiod_set_value_cansleep(reset, 1); + + /* Identify Lochnagar */ + lochnagar->type = config->type; + + lochnagar->regmap = devm_regmap_init_i2c(i2c, config->regmap); + if (IS_ERR(lochnagar->regmap)) { + ret = PTR_ERR(lochnagar->regmap); + dev_err(dev, "Failed to allocate register map: %d\n", ret); + return ret; + } + + /* Wait for Lochnagar to boot */ + ret = lochnagar_wait_for_boot(lochnagar->regmap, &val); + if (ret < 0) { + dev_err(dev, "Failed to read device ID: %d\n", ret); + return ret; + } + + devid = val & LOCHNAGAR_DEVICE_ID_MASK; + rev = val & LOCHNAGAR_REV_ID_MASK; + + if (devid != config->id) { + dev_err(dev, + "ID does not match %s (expected 0x%x got 0x%x)\n", + config->name, config->id, devid); + return -ENODEV; + } + + /* Identify firmware */ + ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID1, &val); + if (ret < 0) { + dev_err(dev, "Failed to read firmware id 1: %d\n", ret); + return ret; + } + + firmwareid = val; + + ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID2, &val); + if (ret < 0) { + dev_err(dev, "Failed to read firmware id 2: %d\n", ret); + return ret; + } + + firmwareid |= (val << config->regmap->val_bits); + + dev_info(dev, "Found %s (0x%x) revision %u firmware 0x%.6x\n", + config->name, devid, rev + 1, firmwareid); + + ret = regmap_register_patch(lochnagar->regmap, config->patch, + config->npatch); + if (ret < 0) { + dev_err(dev, "Failed to register patch: %d\n", ret); + return ret; + } + + ret = devm_of_platform_populate(dev); + if (ret < 0) { + dev_err(dev, "Failed to populate child nodes: %d\n", ret); + return ret; + } + + return ret; +} + +static struct i2c_driver lochnagar_i2c_driver = { + .driver = { + .name = "lochnagar", + .of_match_table = lochnagar_of_match, + .suppress_bind_attrs = true, + }, + .probe = lochnagar_i2c_probe, +}; + +static int __init lochnagar_i2c_init(void) +{ + int ret; + + ret = i2c_add_driver(&lochnagar_i2c_driver); + if (ret) + pr_err("Failed to register Lochnagar driver: %d\n", ret); + + return ret; +} +subsys_initcall(lochnagar_i2c_init); 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