1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * SPI access driver for TI TPS65224/TPS6594/TPS6593/LP8764 PMICs 4 * 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 5 18 #define TPS6594_SPI_READ_BIT BIT(4) 19 20 static bool enable_crc; 21 module_param(enable_crc, bool, 0444); 22 MODULE_PARM_DESC(enable_crc, "Enable CRC feature for SPI interface"); 23 24 DECLARE_CRC8_TABLE(tps6594_spi_crc_table); 25 26 static 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 52 static 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 69 static 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 80 static 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 }; 87 MODULE_DEVICE_TABLE(of, tps6594_spi_of_match_table); 88 89 static 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 } 121 122 static 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 }; 129 module_spi_driver(tps6594_spi_driver); 130 131 MODULE_AUTHOR("Julien Panis <jpanis@baylibre.com>"); 132 MODULE_DESCRIPTION("SPI Interface Driver for TPS65224, TPS6594/3, and LP8764"); 133 MODULE_LICENSE("GPL"); 134