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1// SPDX-License-Identifier: GPL-2.02/*3 * SPI access driver for TI TPS65224/TPS6594/TPS6593/LP8764 PMICs4 *5 * Copyright (C) 2023 BayLibre Incorporated - https://www.baylibre.com/6 */7 8#include <linux/crc8.h>9#include <linux/module.h>10#include <linux/mod_devicetable.h>11#include <linux/of_device.h>12#include <linux/regmap.h>13#include <linux/spi/spi.h>14 15#include <linux/mfd/tps6594.h>16 17#define TPS6594_SPI_PAGE_SHIFT 518#define TPS6594_SPI_READ_BIT BIT(4)19 20static bool enable_crc;21module_param(enable_crc, bool, 0444);22MODULE_PARM_DESC(enable_crc, "Enable CRC feature for SPI interface");23 24DECLARE_CRC8_TABLE(tps6594_spi_crc_table);25 26static int tps6594_spi_reg_read(void *context, unsigned int reg, unsigned int *val)27{28 struct spi_device *spi = context;29 struct tps6594 *tps = spi_get_drvdata(spi);30 u8 buf[4] = { 0 };31 size_t count_rx = 1;32 int ret;33 34 buf[0] = reg;35 buf[1] = TPS6594_REG_TO_PAGE(reg) << TPS6594_SPI_PAGE_SHIFT | TPS6594_SPI_READ_BIT;36 37 if (tps->use_crc)38 count_rx++;39 40 ret = spi_write_then_read(spi, buf, 2, buf + 2, count_rx);41 if (ret < 0)42 return ret;43 44 if (tps->use_crc && buf[3] != crc8(tps6594_spi_crc_table, buf, 3, CRC8_INIT_VALUE))45 return -EIO;46 47 *val = buf[2];48 49 return 0;50}51 52static int tps6594_spi_reg_write(void *context, unsigned int reg, unsigned int val)53{54 struct spi_device *spi = context;55 struct tps6594 *tps = spi_get_drvdata(spi);56 u8 buf[4] = { 0 };57 size_t count = 3;58 59 buf[0] = reg;60 buf[1] = TPS6594_REG_TO_PAGE(reg) << TPS6594_SPI_PAGE_SHIFT;61 buf[2] = val;62 63 if (tps->use_crc)64 buf[3] = crc8(tps6594_spi_crc_table, buf, count++, CRC8_INIT_VALUE);65 66 return spi_write(spi, buf, count);67}68 69static struct regmap_config tps6594_spi_regmap_config = {70 .reg_bits = 16,71 .val_bits = 8,72 .max_register = TPS6594_REG_DWD_FAIL_CNT_REG,73 .volatile_table = &tps6594_volatile_table,74 .reg_read = tps6594_spi_reg_read,75 .reg_write = tps6594_spi_reg_write,76 .use_single_read = true,77 .use_single_write = true,78};79 80static const struct of_device_id tps6594_spi_of_match_table[] = {81 { .compatible = "ti,tps6594-q1", .data = (void *)TPS6594, },82 { .compatible = "ti,tps6593-q1", .data = (void *)TPS6593, },83 { .compatible = "ti,lp8764-q1", .data = (void *)LP8764, },84 { .compatible = "ti,tps65224-q1", .data = (void *)TPS65224, },85 {}86};87MODULE_DEVICE_TABLE(of, tps6594_spi_of_match_table);88 89static int tps6594_spi_probe(struct spi_device *spi)90{91 struct device *dev = &spi->dev;92 struct tps6594 *tps;93 const struct of_device_id *match;94 95 tps = devm_kzalloc(dev, sizeof(*tps), GFP_KERNEL);96 if (!tps)97 return -ENOMEM;98 99 spi_set_drvdata(spi, tps);100 101 tps->dev = dev;102 tps->reg = spi_get_chipselect(spi, 0);103 tps->irq = spi->irq;104 105 match = of_match_device(tps6594_spi_of_match_table, dev);106 if (!match)107 return dev_err_probe(dev, -EINVAL, "Failed to find matching chip ID\n");108 tps->chip_id = (unsigned long)match->data;109 110 if (tps->chip_id == TPS65224)111 tps6594_spi_regmap_config.volatile_table = &tps65224_volatile_table;112 113 tps->regmap = devm_regmap_init(dev, NULL, spi, &tps6594_spi_regmap_config);114 if (IS_ERR(tps->regmap))115 return dev_err_probe(dev, PTR_ERR(tps->regmap), "Failed to init regmap\n");116 117 crc8_populate_msb(tps6594_spi_crc_table, TPS6594_CRC8_POLYNOMIAL);118 119 return tps6594_device_init(tps, enable_crc);120}121 122static struct spi_driver tps6594_spi_driver = {123 .driver = {124 .name = "tps6594",125 .of_match_table = tps6594_spi_of_match_table,126 },127 .probe = tps6594_spi_probe,128};129module_spi_driver(tps6594_spi_driver);130 131MODULE_AUTHOR("Julien Panis <jpanis@baylibre.com>");132MODULE_DESCRIPTION("SPI Interface Driver for TPS65224, TPS6594/3, and LP8764");133MODULE_LICENSE("GPL");134