1567ec716SBartosz Golaszewski // SPDX-License-Identifier: GPL-2.0-or-later 25195e509SWolfram Sang /* 35195e509SWolfram Sang * at24.c - handle most I2C EEPROMs 45195e509SWolfram Sang * 55195e509SWolfram Sang * Copyright (C) 2005-2007 David Brownell 65195e509SWolfram Sang * Copyright (C) 2008 Wolfram Sang, Pengutronix 75195e509SWolfram Sang */ 84ac0d3fbSBartosz Golaszewski 940d8edc9SAndy Shevchenko #include <linux/acpi.h> 1069afc4b6SBartosz Golaszewski #include <linux/bitops.h> 11a4423cedSJean Delvare #include <linux/capability.h> 1269afc4b6SBartosz Golaszewski #include <linux/delay.h> 1369afc4b6SBartosz Golaszewski #include <linux/i2c.h> 1469afc4b6SBartosz Golaszewski #include <linux/init.h> 1569afc4b6SBartosz Golaszewski #include <linux/jiffies.h> 1669afc4b6SBartosz Golaszewski #include <linux/kernel.h> 1769afc4b6SBartosz Golaszewski #include <linux/mod_devicetable.h> 1869afc4b6SBartosz Golaszewski #include <linux/module.h> 1969afc4b6SBartosz Golaszewski #include <linux/mutex.h> 2069afc4b6SBartosz Golaszewski #include <linux/nvmem-provider.h> 2169afc4b6SBartosz Golaszewski #include <linux/of_device.h> 2269afc4b6SBartosz Golaszewski #include <linux/pm_runtime.h> 2369afc4b6SBartosz Golaszewski #include <linux/property.h> 2469afc4b6SBartosz Golaszewski #include <linux/regmap.h> 25cd5676dbSBibby Hsieh #include <linux/regulator/consumer.h> 2669afc4b6SBartosz Golaszewski #include <linux/slab.h> 275195e509SWolfram Sang 284fa882c9SBartosz Golaszewski /* Address pointer is 16 bit. */ 294fa882c9SBartosz Golaszewski #define AT24_FLAG_ADDR16 BIT(7) 304fa882c9SBartosz Golaszewski /* sysfs-entry will be read-only. */ 314fa882c9SBartosz Golaszewski #define AT24_FLAG_READONLY BIT(6) 324fa882c9SBartosz Golaszewski /* sysfs-entry will be world-readable. */ 334fa882c9SBartosz Golaszewski #define AT24_FLAG_IRUGO BIT(5) 344fa882c9SBartosz Golaszewski /* Take always 8 addresses (24c00). */ 354fa882c9SBartosz Golaszewski #define AT24_FLAG_TAKE8ADDR BIT(4) 364fa882c9SBartosz Golaszewski /* Factory-programmed serial number. */ 374fa882c9SBartosz Golaszewski #define AT24_FLAG_SERIAL BIT(3) 384fa882c9SBartosz Golaszewski /* Factory-programmed mac address. */ 394fa882c9SBartosz Golaszewski #define AT24_FLAG_MAC BIT(2) 404fa882c9SBartosz Golaszewski /* Does not auto-rollover reads to the next slave address. */ 414fa882c9SBartosz Golaszewski #define AT24_FLAG_NO_RDROL BIT(1) 424fa882c9SBartosz Golaszewski 435195e509SWolfram Sang /* 445195e509SWolfram Sang * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable. 455195e509SWolfram Sang * Differences between different vendor product lines (like Atmel AT24C or 465195e509SWolfram Sang * MicroChip 24LC, etc) won't much matter for typical read/write access. 475195e509SWolfram Sang * There are also I2C RAM chips, likewise interchangeable. One example 485195e509SWolfram Sang * would be the PCF8570, which acts like a 24c02 EEPROM (256 bytes). 495195e509SWolfram Sang * 505195e509SWolfram Sang * However, misconfiguration can lose data. "Set 16-bit memory address" 515195e509SWolfram Sang * to a part with 8-bit addressing will overwrite data. Writing with too 525195e509SWolfram Sang * big a page size also loses data. And it's not safe to assume that the 535195e509SWolfram Sang * conventional addresses 0x50..0x57 only hold eeproms; a PCF8563 RTC 545195e509SWolfram Sang * uses 0x51, for just one example. 555195e509SWolfram Sang * 565195e509SWolfram Sang * Accordingly, explicit board-specific configuration data should be used 575195e509SWolfram Sang * in almost all cases. (One partial exception is an SMBus used to access 585195e509SWolfram Sang * "SPD" data for DRAM sticks. Those only use 24c02 EEPROMs.) 595195e509SWolfram Sang * 605195e509SWolfram Sang * So this driver uses "new style" I2C driver binding, expecting to be 615195e509SWolfram Sang * told what devices exist. That may be in arch/X/mach-Y/board-Z.c or 625195e509SWolfram Sang * similar kernel-resident tables; or, configuration data coming from 635195e509SWolfram Sang * a bootloader. 645195e509SWolfram Sang * 655195e509SWolfram Sang * Other than binding model, current differences from "eeprom" driver are 665195e509SWolfram Sang * that this one handles write access and isn't restricted to 24c02 devices. 675195e509SWolfram Sang * It also handles larger devices (32 kbit and up) with two-byte addresses, 685195e509SWolfram Sang * which won't work on pure SMBus systems. 695195e509SWolfram Sang */ 705195e509SWolfram Sang 715c015258SHeiner Kallweit struct at24_client { 725c015258SHeiner Kallweit struct i2c_client *client; 735c015258SHeiner Kallweit struct regmap *regmap; 745c015258SHeiner Kallweit }; 755c015258SHeiner Kallweit 765195e509SWolfram Sang struct at24_data { 775195e509SWolfram Sang /* 785195e509SWolfram Sang * Lock protects against activities from other Linux tasks, 795195e509SWolfram Sang * but not from changes by other I2C masters. 805195e509SWolfram Sang */ 815195e509SWolfram Sang struct mutex lock; 825195e509SWolfram Sang 83aa4ce228SBartosz Golaszewski unsigned int write_max; 84aa4ce228SBartosz Golaszewski unsigned int num_addresses; 854bb5c13cSHeiner Kallweit unsigned int offset_adj; 865195e509SWolfram Sang 877c280664SBartosz Golaszewski u32 byte_len; 887c280664SBartosz Golaszewski u16 page_size; 897c280664SBartosz Golaszewski u8 flags; 907c280664SBartosz Golaszewski 9157d15550SAndrew Lunn struct nvmem_device *nvmem; 92cd5676dbSBibby Hsieh struct regulator *vcc_reg; 93a4423cedSJean Delvare void (*read_post)(unsigned int off, char *buf, size_t count); 9457d15550SAndrew Lunn 955195e509SWolfram Sang /* 965195e509SWolfram Sang * Some chips tie up multiple I2C addresses; dummy devices reserve 975195e509SWolfram Sang * them for us, and we'll use them with SMBus calls. 985195e509SWolfram Sang */ 995c015258SHeiner Kallweit struct at24_client client[]; 1005195e509SWolfram Sang }; 1015195e509SWolfram Sang 1025195e509SWolfram Sang /* 1035195e509SWolfram Sang * This parameter is to help this driver avoid blocking other drivers out 1045195e509SWolfram Sang * of I2C for potentially troublesome amounts of time. With a 100 kHz I2C 1055195e509SWolfram Sang * clock, one 256 byte read takes about 1/43 second which is excessive; 1065195e509SWolfram Sang * but the 1/170 second it takes at 400 kHz may be quite reasonable; and 1075195e509SWolfram Sang * at 1 MHz (Fm+) a 1/430 second delay could easily be invisible. 1085195e509SWolfram Sang * 1095195e509SWolfram Sang * This value is forced to be a power of two so that writes align on pages. 1105195e509SWolfram Sang */ 111ec3c2d51SBartosz Golaszewski static unsigned int at24_io_limit = 128; 112ec3c2d51SBartosz Golaszewski module_param_named(io_limit, at24_io_limit, uint, 0); 113ec3c2d51SBartosz Golaszewski MODULE_PARM_DESC(at24_io_limit, "Maximum bytes per I/O (default 128)"); 1145195e509SWolfram Sang 1155195e509SWolfram Sang /* 1165195e509SWolfram Sang * Specs often allow 5 msec for a page write, sometimes 20 msec; 1175195e509SWolfram Sang * it's important to recover from write timeouts. 1185195e509SWolfram Sang */ 119ec3c2d51SBartosz Golaszewski static unsigned int at24_write_timeout = 25; 120ec3c2d51SBartosz Golaszewski module_param_named(write_timeout, at24_write_timeout, uint, 0); 121ec3c2d51SBartosz Golaszewski MODULE_PARM_DESC(at24_write_timeout, "Time (in ms) to try writes (default 25)"); 1225195e509SWolfram Sang 123b680f4faSSven Van Asbroeck struct at24_chip_data { 124b680f4faSSven Van Asbroeck u32 byte_len; 125b680f4faSSven Van Asbroeck u8 flags; 126a4423cedSJean Delvare void (*read_post)(unsigned int off, char *buf, size_t count); 127b680f4faSSven Van Asbroeck }; 128b680f4faSSven Van Asbroeck 129b680f4faSSven Van Asbroeck #define AT24_CHIP_DATA(_name, _len, _flags) \ 130b680f4faSSven Van Asbroeck static const struct at24_chip_data _name = { \ 131b680f4faSSven Van Asbroeck .byte_len = _len, .flags = _flags, \ 132b680f4faSSven Van Asbroeck } 133b680f4faSSven Van Asbroeck 134a4423cedSJean Delvare #define AT24_CHIP_DATA_CB(_name, _len, _flags, _read_post) \ 135a4423cedSJean Delvare static const struct at24_chip_data _name = { \ 136a4423cedSJean Delvare .byte_len = _len, .flags = _flags, \ 137a4423cedSJean Delvare .read_post = _read_post, \ 138a4423cedSJean Delvare } 139a4423cedSJean Delvare 140a4423cedSJean Delvare static void at24_read_post_vaio(unsigned int off, char *buf, size_t count) 141a4423cedSJean Delvare { 142a4423cedSJean Delvare int i; 143a4423cedSJean Delvare 144a4423cedSJean Delvare if (capable(CAP_SYS_ADMIN)) 145a4423cedSJean Delvare return; 146a4423cedSJean Delvare 147a4423cedSJean Delvare /* 148a4423cedSJean Delvare * Hide VAIO private settings to regular users: 149a4423cedSJean Delvare * - BIOS passwords: bytes 0x00 to 0x0f 150a4423cedSJean Delvare * - UUID: bytes 0x10 to 0x1f 151a4423cedSJean Delvare * - Serial number: 0xc0 to 0xdf 152a4423cedSJean Delvare */ 153a4423cedSJean Delvare for (i = 0; i < count; i++) { 154a4423cedSJean Delvare if ((off + i <= 0x1f) || 155a4423cedSJean Delvare (off + i >= 0xc0 && off + i <= 0xdf)) 156a4423cedSJean Delvare buf[i] = 0; 157a4423cedSJean Delvare } 158a4423cedSJean Delvare } 159a4423cedSJean Delvare 1605195e509SWolfram Sang /* needs 8 addresses as A0-A2 are ignored */ 161b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c00, 128 / 8, AT24_FLAG_TAKE8ADDR); 1625195e509SWolfram Sang /* old variants can't be handled with this generic entry! */ 163b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c01, 1024 / 8, 0); 164b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24cs01, 16, 165b680f4faSSven Van Asbroeck AT24_FLAG_SERIAL | AT24_FLAG_READONLY); 166b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c02, 2048 / 8, 0); 167b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24cs02, 16, 168b680f4faSSven Van Asbroeck AT24_FLAG_SERIAL | AT24_FLAG_READONLY); 169b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24mac402, 48 / 8, 170b680f4faSSven Van Asbroeck AT24_FLAG_MAC | AT24_FLAG_READONLY); 171b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24mac602, 64 / 8, 172b680f4faSSven Van Asbroeck AT24_FLAG_MAC | AT24_FLAG_READONLY); 1735195e509SWolfram Sang /* spd is a 24c02 in memory DIMMs */ 174b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_spd, 2048 / 8, 175b680f4faSSven Van Asbroeck AT24_FLAG_READONLY | AT24_FLAG_IRUGO); 176a4423cedSJean Delvare /* 24c02_vaio is a 24c02 on some Sony laptops */ 177a4423cedSJean Delvare AT24_CHIP_DATA_CB(at24_data_24c02_vaio, 2048 / 8, 178a4423cedSJean Delvare AT24_FLAG_READONLY | AT24_FLAG_IRUGO, 179a4423cedSJean Delvare at24_read_post_vaio); 180b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c04, 4096 / 8, 0); 181b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24cs04, 16, 182b680f4faSSven Van Asbroeck AT24_FLAG_SERIAL | AT24_FLAG_READONLY); 1835195e509SWolfram Sang /* 24rf08 quirk is handled at i2c-core */ 184b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c08, 8192 / 8, 0); 185b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24cs08, 16, 186b680f4faSSven Van Asbroeck AT24_FLAG_SERIAL | AT24_FLAG_READONLY); 187b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c16, 16384 / 8, 0); 188b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24cs16, 16, 189b680f4faSSven Van Asbroeck AT24_FLAG_SERIAL | AT24_FLAG_READONLY); 190b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c32, 32768 / 8, AT24_FLAG_ADDR16); 191b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24cs32, 16, 192b680f4faSSven Van Asbroeck AT24_FLAG_ADDR16 | AT24_FLAG_SERIAL | AT24_FLAG_READONLY); 193b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c64, 65536 / 8, AT24_FLAG_ADDR16); 194b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24cs64, 16, 195b680f4faSSven Van Asbroeck AT24_FLAG_ADDR16 | AT24_FLAG_SERIAL | AT24_FLAG_READONLY); 196b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c128, 131072 / 8, AT24_FLAG_ADDR16); 197b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c256, 262144 / 8, AT24_FLAG_ADDR16); 198b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c512, 524288 / 8, AT24_FLAG_ADDR16); 199b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_24c1024, 1048576 / 8, AT24_FLAG_ADDR16); 20037cf28d3SAdrian Bunk AT24_CHIP_DATA(at24_data_24c2048, 2097152 / 8, AT24_FLAG_ADDR16); 201b680f4faSSven Van Asbroeck /* identical to 24c08 ? */ 202b680f4faSSven Van Asbroeck AT24_CHIP_DATA(at24_data_INT3499, 8192 / 8, 0); 203b680f4faSSven Van Asbroeck 204b680f4faSSven Van Asbroeck static const struct i2c_device_id at24_ids[] = { 205b680f4faSSven Van Asbroeck { "24c00", (kernel_ulong_t)&at24_data_24c00 }, 206b680f4faSSven Van Asbroeck { "24c01", (kernel_ulong_t)&at24_data_24c01 }, 207b680f4faSSven Van Asbroeck { "24cs01", (kernel_ulong_t)&at24_data_24cs01 }, 208b680f4faSSven Van Asbroeck { "24c02", (kernel_ulong_t)&at24_data_24c02 }, 209b680f4faSSven Van Asbroeck { "24cs02", (kernel_ulong_t)&at24_data_24cs02 }, 210b680f4faSSven Van Asbroeck { "24mac402", (kernel_ulong_t)&at24_data_24mac402 }, 211b680f4faSSven Van Asbroeck { "24mac602", (kernel_ulong_t)&at24_data_24mac602 }, 212b680f4faSSven Van Asbroeck { "spd", (kernel_ulong_t)&at24_data_spd }, 213a4423cedSJean Delvare { "24c02-vaio", (kernel_ulong_t)&at24_data_24c02_vaio }, 214b680f4faSSven Van Asbroeck { "24c04", (kernel_ulong_t)&at24_data_24c04 }, 215b680f4faSSven Van Asbroeck { "24cs04", (kernel_ulong_t)&at24_data_24cs04 }, 216b680f4faSSven Van Asbroeck { "24c08", (kernel_ulong_t)&at24_data_24c08 }, 217b680f4faSSven Van Asbroeck { "24cs08", (kernel_ulong_t)&at24_data_24cs08 }, 218b680f4faSSven Van Asbroeck { "24c16", (kernel_ulong_t)&at24_data_24c16 }, 219b680f4faSSven Van Asbroeck { "24cs16", (kernel_ulong_t)&at24_data_24cs16 }, 220b680f4faSSven Van Asbroeck { "24c32", (kernel_ulong_t)&at24_data_24c32 }, 221b680f4faSSven Van Asbroeck { "24cs32", (kernel_ulong_t)&at24_data_24cs32 }, 222b680f4faSSven Van Asbroeck { "24c64", (kernel_ulong_t)&at24_data_24c64 }, 223b680f4faSSven Van Asbroeck { "24cs64", (kernel_ulong_t)&at24_data_24cs64 }, 224b680f4faSSven Van Asbroeck { "24c128", (kernel_ulong_t)&at24_data_24c128 }, 225b680f4faSSven Van Asbroeck { "24c256", (kernel_ulong_t)&at24_data_24c256 }, 226b680f4faSSven Van Asbroeck { "24c512", (kernel_ulong_t)&at24_data_24c512 }, 227b680f4faSSven Van Asbroeck { "24c1024", (kernel_ulong_t)&at24_data_24c1024 }, 22837cf28d3SAdrian Bunk { "24c2048", (kernel_ulong_t)&at24_data_24c2048 }, 2295195e509SWolfram Sang { "at24", 0 }, 2305195e509SWolfram Sang { /* END OF LIST */ } 2315195e509SWolfram Sang }; 2325195e509SWolfram Sang MODULE_DEVICE_TABLE(i2c, at24_ids); 2335195e509SWolfram Sang 2347f2a2f0dSJavier Martinez Canillas static const struct of_device_id at24_of_match[] = { 235b680f4faSSven Van Asbroeck { .compatible = "atmel,24c00", .data = &at24_data_24c00 }, 236b680f4faSSven Van Asbroeck { .compatible = "atmel,24c01", .data = &at24_data_24c01 }, 2370f30aca7SBartosz Golaszewski { .compatible = "atmel,24cs01", .data = &at24_data_24cs01 }, 238b680f4faSSven Van Asbroeck { .compatible = "atmel,24c02", .data = &at24_data_24c02 }, 2390f30aca7SBartosz Golaszewski { .compatible = "atmel,24cs02", .data = &at24_data_24cs02 }, 2400f30aca7SBartosz Golaszewski { .compatible = "atmel,24mac402", .data = &at24_data_24mac402 }, 2410f30aca7SBartosz Golaszewski { .compatible = "atmel,24mac602", .data = &at24_data_24mac602 }, 242b680f4faSSven Van Asbroeck { .compatible = "atmel,spd", .data = &at24_data_spd }, 243b680f4faSSven Van Asbroeck { .compatible = "atmel,24c04", .data = &at24_data_24c04 }, 2440f30aca7SBartosz Golaszewski { .compatible = "atmel,24cs04", .data = &at24_data_24cs04 }, 245b680f4faSSven Van Asbroeck { .compatible = "atmel,24c08", .data = &at24_data_24c08 }, 2460f30aca7SBartosz Golaszewski { .compatible = "atmel,24cs08", .data = &at24_data_24cs08 }, 247b680f4faSSven Van Asbroeck { .compatible = "atmel,24c16", .data = &at24_data_24c16 }, 2480f30aca7SBartosz Golaszewski { .compatible = "atmel,24cs16", .data = &at24_data_24cs16 }, 249b680f4faSSven Van Asbroeck { .compatible = "atmel,24c32", .data = &at24_data_24c32 }, 2500f30aca7SBartosz Golaszewski { .compatible = "atmel,24cs32", .data = &at24_data_24cs32 }, 251b680f4faSSven Van Asbroeck { .compatible = "atmel,24c64", .data = &at24_data_24c64 }, 2520f30aca7SBartosz Golaszewski { .compatible = "atmel,24cs64", .data = &at24_data_24cs64 }, 253b680f4faSSven Van Asbroeck { .compatible = "atmel,24c128", .data = &at24_data_24c128 }, 254b680f4faSSven Van Asbroeck { .compatible = "atmel,24c256", .data = &at24_data_24c256 }, 255b680f4faSSven Van Asbroeck { .compatible = "atmel,24c512", .data = &at24_data_24c512 }, 256b680f4faSSven Van Asbroeck { .compatible = "atmel,24c1024", .data = &at24_data_24c1024 }, 25737cf28d3SAdrian Bunk { .compatible = "atmel,24c2048", .data = &at24_data_24c2048 }, 258b680f4faSSven Van Asbroeck { /* END OF LIST */ }, 2597f2a2f0dSJavier Martinez Canillas }; 2607f2a2f0dSJavier Martinez Canillas MODULE_DEVICE_TABLE(of, at24_of_match); 2617f2a2f0dSJavier Martinez Canillas 2628965930cSLee Jones static const struct acpi_device_id __maybe_unused at24_acpi_ids[] = { 263b680f4faSSven Van Asbroeck { "INT3499", (kernel_ulong_t)&at24_data_INT3499 }, 2644837621cSMarkus Pietrek { "TPF0001", (kernel_ulong_t)&at24_data_24c1024 }, 265b680f4faSSven Van Asbroeck { /* END OF LIST */ } 26640d8edc9SAndy Shevchenko }; 26740d8edc9SAndy Shevchenko MODULE_DEVICE_TABLE(acpi, at24_acpi_ids); 26840d8edc9SAndy Shevchenko 2695195e509SWolfram Sang /* 2705195e509SWolfram Sang * This routine supports chips which consume multiple I2C addresses. It 2715195e509SWolfram Sang * computes the addressing information to be used for a given r/w request. 2725195e509SWolfram Sang * Assumes that sanity checks for offset happened at sysfs-layer. 2739afd6866SBartosz Golaszewski * 2749afd6866SBartosz Golaszewski * Slave address and byte offset derive from the offset. Always 2759afd6866SBartosz Golaszewski * set the byte address; on a multi-master board, another master 2769afd6866SBartosz Golaszewski * may have changed the chip's "current" address pointer. 2775195e509SWolfram Sang */ 27846049486SHeiner Kallweit static struct at24_client *at24_translate_offset(struct at24_data *at24, 2792da78ac3SBartosz Golaszewski unsigned int *offset) 2805195e509SWolfram Sang { 281aa4ce228SBartosz Golaszewski unsigned int i; 2825195e509SWolfram Sang 2837c280664SBartosz Golaszewski if (at24->flags & AT24_FLAG_ADDR16) { 2845195e509SWolfram Sang i = *offset >> 16; 2855195e509SWolfram Sang *offset &= 0xffff; 2865195e509SWolfram Sang } else { 2875195e509SWolfram Sang i = *offset >> 8; 2885195e509SWolfram Sang *offset &= 0xff; 2895195e509SWolfram Sang } 2905195e509SWolfram Sang 29146049486SHeiner Kallweit return &at24->client[i]; 2925195e509SWolfram Sang } 2935195e509SWolfram Sang 294f1a640c5SBartosz Golaszewski static struct device *at24_base_client_dev(struct at24_data *at24) 295f1a640c5SBartosz Golaszewski { 296f1a640c5SBartosz Golaszewski return &at24->client[0].client->dev; 297f1a640c5SBartosz Golaszewski } 298f1a640c5SBartosz Golaszewski 299e32213fbSSven Van Asbroeck static size_t at24_adjust_read_count(struct at24_data *at24, 300e32213fbSSven Van Asbroeck unsigned int offset, size_t count) 301e32213fbSSven Van Asbroeck { 302e32213fbSSven Van Asbroeck unsigned int bits; 303e32213fbSSven Van Asbroeck size_t remainder; 304e32213fbSSven Van Asbroeck 305e32213fbSSven Van Asbroeck /* 306e32213fbSSven Van Asbroeck * In case of multi-address chips that don't rollover reads to 307e32213fbSSven Van Asbroeck * the next slave address: truncate the count to the slave boundary, 308e32213fbSSven Van Asbroeck * so that the read never straddles slaves. 309e32213fbSSven Van Asbroeck */ 3107c280664SBartosz Golaszewski if (at24->flags & AT24_FLAG_NO_RDROL) { 3117c280664SBartosz Golaszewski bits = (at24->flags & AT24_FLAG_ADDR16) ? 16 : 8; 312e32213fbSSven Van Asbroeck remainder = BIT(bits) - offset; 313e32213fbSSven Van Asbroeck if (count > remainder) 314e32213fbSSven Van Asbroeck count = remainder; 315e32213fbSSven Van Asbroeck } 316e32213fbSSven Van Asbroeck 317ec3c2d51SBartosz Golaszewski if (count > at24_io_limit) 318ec3c2d51SBartosz Golaszewski count = at24_io_limit; 319e32213fbSSven Van Asbroeck 320e32213fbSSven Van Asbroeck return count; 321e32213fbSSven Van Asbroeck } 322e32213fbSSven Van Asbroeck 3234bb5c13cSHeiner Kallweit static ssize_t at24_regmap_read(struct at24_data *at24, char *buf, 3244bb5c13cSHeiner Kallweit unsigned int offset, size_t count) 3254bb5c13cSHeiner Kallweit { 3264bb5c13cSHeiner Kallweit unsigned long timeout, read_time; 3274bb5c13cSHeiner Kallweit struct at24_client *at24_client; 3284bb5c13cSHeiner Kallweit struct i2c_client *client; 3294bb5c13cSHeiner Kallweit struct regmap *regmap; 3304bb5c13cSHeiner Kallweit int ret; 3314bb5c13cSHeiner Kallweit 3324bb5c13cSHeiner Kallweit at24_client = at24_translate_offset(at24, &offset); 3334bb5c13cSHeiner Kallweit regmap = at24_client->regmap; 3344bb5c13cSHeiner Kallweit client = at24_client->client; 335e32213fbSSven Van Asbroeck count = at24_adjust_read_count(at24, offset, count); 3364bb5c13cSHeiner Kallweit 3374bb5c13cSHeiner Kallweit /* adjust offset for mac and serial read ops */ 3384bb5c13cSHeiner Kallweit offset += at24->offset_adj; 3394bb5c13cSHeiner Kallweit 3409a9e295eSWang Xin timeout = jiffies + msecs_to_jiffies(at24_write_timeout); 3419a9e295eSWang Xin do { 3429a9e295eSWang Xin /* 3439a9e295eSWang Xin * The timestamp shall be taken before the actual operation 3449a9e295eSWang Xin * to avoid a premature timeout in case of high CPU load. 3459a9e295eSWang Xin */ 3469a9e295eSWang Xin read_time = jiffies; 3479a9e295eSWang Xin 3484bb5c13cSHeiner Kallweit ret = regmap_bulk_read(regmap, offset, buf, count); 3494bb5c13cSHeiner Kallweit dev_dbg(&client->dev, "read %zu@%d --> %d (%ld)\n", 3504bb5c13cSHeiner Kallweit count, offset, ret, jiffies); 3514bb5c13cSHeiner Kallweit if (!ret) 3524bb5c13cSHeiner Kallweit return count; 3539a9e295eSWang Xin 3549a9e295eSWang Xin usleep_range(1000, 1500); 3559a9e295eSWang Xin } while (time_before(read_time, timeout)); 3564bb5c13cSHeiner Kallweit 3574bb5c13cSHeiner Kallweit return -ETIMEDOUT; 3584bb5c13cSHeiner Kallweit } 3594bb5c13cSHeiner Kallweit 3605195e509SWolfram Sang /* 3615195e509SWolfram Sang * Note that if the hardware write-protect pin is pulled high, the whole 3625195e509SWolfram Sang * chip is normally write protected. But there are plenty of product 3635195e509SWolfram Sang * variants here, including OTP fuses and partial chip protect. 3645195e509SWolfram Sang * 365cd0c8615SBartosz Golaszewski * We only use page mode writes; the alternative is sloooow. These routines 366cd0c8615SBartosz Golaszewski * write at most one page. 3675195e509SWolfram Sang */ 368cd0c8615SBartosz Golaszewski 369cd0c8615SBartosz Golaszewski static size_t at24_adjust_write_count(struct at24_data *at24, 3702da78ac3SBartosz Golaszewski unsigned int offset, size_t count) 3715195e509SWolfram Sang { 372aa4ce228SBartosz Golaszewski unsigned int next_page; 3735195e509SWolfram Sang 3745195e509SWolfram Sang /* write_max is at most a page */ 3755195e509SWolfram Sang if (count > at24->write_max) 3765195e509SWolfram Sang count = at24->write_max; 3775195e509SWolfram Sang 3785195e509SWolfram Sang /* Never roll over backwards, to the start of this page */ 3797c280664SBartosz Golaszewski next_page = roundup(offset + 1, at24->page_size); 3805195e509SWolfram Sang if (offset + count > next_page) 3815195e509SWolfram Sang count = next_page - offset; 3825195e509SWolfram Sang 383cd0c8615SBartosz Golaszewski return count; 384cd0c8615SBartosz Golaszewski } 385cd0c8615SBartosz Golaszewski 3868e5888e1SHeiner Kallweit static ssize_t at24_regmap_write(struct at24_data *at24, const char *buf, 3878e5888e1SHeiner Kallweit unsigned int offset, size_t count) 3888e5888e1SHeiner Kallweit { 3898e5888e1SHeiner Kallweit unsigned long timeout, write_time; 3908e5888e1SHeiner Kallweit struct at24_client *at24_client; 3918e5888e1SHeiner Kallweit struct i2c_client *client; 3928e5888e1SHeiner Kallweit struct regmap *regmap; 3938e5888e1SHeiner Kallweit int ret; 3948e5888e1SHeiner Kallweit 3958e5888e1SHeiner Kallweit at24_client = at24_translate_offset(at24, &offset); 3968e5888e1SHeiner Kallweit regmap = at24_client->regmap; 3978e5888e1SHeiner Kallweit client = at24_client->client; 3988e5888e1SHeiner Kallweit count = at24_adjust_write_count(at24, offset, count); 3999a9e295eSWang Xin timeout = jiffies + msecs_to_jiffies(at24_write_timeout); 4008e5888e1SHeiner Kallweit 4019a9e295eSWang Xin do { 4029a9e295eSWang Xin /* 4039a9e295eSWang Xin * The timestamp shall be taken before the actual operation 4049a9e295eSWang Xin * to avoid a premature timeout in case of high CPU load. 4059a9e295eSWang Xin */ 4069a9e295eSWang Xin write_time = jiffies; 4079a9e295eSWang Xin 4088e5888e1SHeiner Kallweit ret = regmap_bulk_write(regmap, offset, buf, count); 4098e5888e1SHeiner Kallweit dev_dbg(&client->dev, "write %zu@%d --> %d (%ld)\n", 4108e5888e1SHeiner Kallweit count, offset, ret, jiffies); 4118e5888e1SHeiner Kallweit if (!ret) 4128e5888e1SHeiner Kallweit return count; 4139a9e295eSWang Xin 4149a9e295eSWang Xin usleep_range(1000, 1500); 4159a9e295eSWang Xin } while (time_before(write_time, timeout)); 4168e5888e1SHeiner Kallweit 4178e5888e1SHeiner Kallweit return -ETIMEDOUT; 4188e5888e1SHeiner Kallweit } 4198e5888e1SHeiner Kallweit 420d5bc0047SBartosz Golaszewski static int at24_read(void *priv, unsigned int off, void *val, size_t count) 421d5bc0047SBartosz Golaszewski { 4225ca2b5b7SBartosz Golaszewski struct at24_data *at24; 4235ca2b5b7SBartosz Golaszewski struct device *dev; 424d5bc0047SBartosz Golaszewski char *buf = val; 42599363d1cSJean Delvare int i, ret; 426d5bc0047SBartosz Golaszewski 4275ca2b5b7SBartosz Golaszewski at24 = priv; 428f1a640c5SBartosz Golaszewski dev = at24_base_client_dev(at24); 4295ca2b5b7SBartosz Golaszewski 430d5bc0047SBartosz Golaszewski if (unlikely(!count)) 431d5bc0047SBartosz Golaszewski return count; 432d5bc0047SBartosz Golaszewski 4337c280664SBartosz Golaszewski if (off + count > at24->byte_len) 434d9bcd462SHeiner Kallweit return -EINVAL; 435d9bcd462SHeiner Kallweit 436f9ecc83fSSakari Ailus ret = pm_runtime_get_sync(dev); 43798e82010SDivagar Mohandass if (ret < 0) { 438f9ecc83fSSakari Ailus pm_runtime_put_noidle(dev); 43998e82010SDivagar Mohandass return ret; 44098e82010SDivagar Mohandass } 44198e82010SDivagar Mohandass 442d5bc0047SBartosz Golaszewski /* 443d5bc0047SBartosz Golaszewski * Read data from chip, protecting against concurrent updates 444d5bc0047SBartosz Golaszewski * from this host, but not from other I2C masters. 445d5bc0047SBartosz Golaszewski */ 446d5bc0047SBartosz Golaszewski mutex_lock(&at24->lock); 447d5bc0047SBartosz Golaszewski 44899363d1cSJean Delvare for (i = 0; count; i += ret, count -= ret) { 44999363d1cSJean Delvare ret = at24_regmap_read(at24, buf + i, off + i, count); 450eb27fde2SBartosz Golaszewski if (ret < 0) { 451d5bc0047SBartosz Golaszewski mutex_unlock(&at24->lock); 452f9ecc83fSSakari Ailus pm_runtime_put(dev); 453eb27fde2SBartosz Golaszewski return ret; 454d5bc0047SBartosz Golaszewski } 455d5bc0047SBartosz Golaszewski } 456d5bc0047SBartosz Golaszewski 457d5bc0047SBartosz Golaszewski mutex_unlock(&at24->lock); 458d5bc0047SBartosz Golaszewski 459f9ecc83fSSakari Ailus pm_runtime_put(dev); 46098e82010SDivagar Mohandass 461a4423cedSJean Delvare if (unlikely(at24->read_post)) 46299363d1cSJean Delvare at24->read_post(off, buf, i); 463a4423cedSJean Delvare 464d5bc0047SBartosz Golaszewski return 0; 465d5bc0047SBartosz Golaszewski } 466d5bc0047SBartosz Golaszewski 467cf0361a2SSrinivas Kandagatla static int at24_write(void *priv, unsigned int off, void *val, size_t count) 4685195e509SWolfram Sang { 4695ca2b5b7SBartosz Golaszewski struct at24_data *at24; 4705ca2b5b7SBartosz Golaszewski struct device *dev; 471cf0361a2SSrinivas Kandagatla char *buf = val; 47298e82010SDivagar Mohandass int ret; 4735195e509SWolfram Sang 4745ca2b5b7SBartosz Golaszewski at24 = priv; 475f1a640c5SBartosz Golaszewski dev = at24_base_client_dev(at24); 4765ca2b5b7SBartosz Golaszewski 4775195e509SWolfram Sang if (unlikely(!count)) 478cf0361a2SSrinivas Kandagatla return -EINVAL; 4795195e509SWolfram Sang 4807c280664SBartosz Golaszewski if (off + count > at24->byte_len) 481d9bcd462SHeiner Kallweit return -EINVAL; 482d9bcd462SHeiner Kallweit 483f9ecc83fSSakari Ailus ret = pm_runtime_get_sync(dev); 48498e82010SDivagar Mohandass if (ret < 0) { 485f9ecc83fSSakari Ailus pm_runtime_put_noidle(dev); 48698e82010SDivagar Mohandass return ret; 48798e82010SDivagar Mohandass } 48898e82010SDivagar Mohandass 4895195e509SWolfram Sang /* 4905195e509SWolfram Sang * Write data to chip, protecting against concurrent updates 4915195e509SWolfram Sang * from this host, but not from other I2C masters. 4925195e509SWolfram Sang */ 4935195e509SWolfram Sang mutex_lock(&at24->lock); 4945195e509SWolfram Sang 4955195e509SWolfram Sang while (count) { 496c4fee330SBartosz Golaszewski ret = at24_regmap_write(at24, buf, off, count); 497c4fee330SBartosz Golaszewski if (ret < 0) { 498cf0361a2SSrinivas Kandagatla mutex_unlock(&at24->lock); 499f9ecc83fSSakari Ailus pm_runtime_put(dev); 500c4fee330SBartosz Golaszewski return ret; 5015195e509SWolfram Sang } 502c4fee330SBartosz Golaszewski buf += ret; 503c4fee330SBartosz Golaszewski off += ret; 504c4fee330SBartosz Golaszewski count -= ret; 5055195e509SWolfram Sang } 5065195e509SWolfram Sang 5075195e509SWolfram Sang mutex_unlock(&at24->lock); 5085195e509SWolfram Sang 509f9ecc83fSSakari Ailus pm_runtime_put(dev); 51098e82010SDivagar Mohandass 51157d15550SAndrew Lunn return 0; 51257d15550SAndrew Lunn } 51357d15550SAndrew Lunn 5144fa882c9SBartosz Golaszewski static const struct at24_chip_data *at24_get_chip_data(struct device *dev) 515feb2f19bSBartosz Golaszewski { 516feb2f19bSBartosz Golaszewski struct device_node *of_node = dev->of_node; 517feb2f19bSBartosz Golaszewski const struct at24_chip_data *cdata; 518feb2f19bSBartosz Golaszewski const struct i2c_device_id *id; 519feb2f19bSBartosz Golaszewski 520feb2f19bSBartosz Golaszewski id = i2c_match_id(at24_ids, to_i2c_client(dev)); 521feb2f19bSBartosz Golaszewski 522feb2f19bSBartosz Golaszewski /* 523feb2f19bSBartosz Golaszewski * The I2C core allows OF nodes compatibles to match against the 524feb2f19bSBartosz Golaszewski * I2C device ID table as a fallback, so check not only if an OF 525feb2f19bSBartosz Golaszewski * node is present but also if it matches an OF device ID entry. 526feb2f19bSBartosz Golaszewski */ 527feb2f19bSBartosz Golaszewski if (of_node && of_match_device(at24_of_match, dev)) 528feb2f19bSBartosz Golaszewski cdata = of_device_get_match_data(dev); 529feb2f19bSBartosz Golaszewski else if (id) 5305fa4d14eSBartosz Golaszewski cdata = (void *)id->driver_data; 531feb2f19bSBartosz Golaszewski else 532feb2f19bSBartosz Golaszewski cdata = acpi_device_get_match_data(dev); 533feb2f19bSBartosz Golaszewski 534feb2f19bSBartosz Golaszewski if (!cdata) 5354fa882c9SBartosz Golaszewski return ERR_PTR(-ENODEV); 536feb2f19bSBartosz Golaszewski 5374fa882c9SBartosz Golaszewski return cdata; 538feb2f19bSBartosz Golaszewski } 539feb2f19bSBartosz Golaszewski 54073b0d922SBartosz Golaszewski static int at24_make_dummy_client(struct at24_data *at24, unsigned int index, 54173b0d922SBartosz Golaszewski struct regmap_config *regmap_config) 54273b0d922SBartosz Golaszewski { 54373b0d922SBartosz Golaszewski struct i2c_client *base_client, *dummy_client; 54473b0d922SBartosz Golaszewski struct regmap *regmap; 54573b0d922SBartosz Golaszewski struct device *dev; 54673b0d922SBartosz Golaszewski 54773b0d922SBartosz Golaszewski base_client = at24->client[0].client; 54873b0d922SBartosz Golaszewski dev = &base_client->dev; 54973b0d922SBartosz Golaszewski 550e7308628SBartosz Golaszewski dummy_client = devm_i2c_new_dummy_device(dev, base_client->adapter, 55173b0d922SBartosz Golaszewski base_client->addr + index); 552e7308628SBartosz Golaszewski if (IS_ERR(dummy_client)) 553e7308628SBartosz Golaszewski return PTR_ERR(dummy_client); 55473b0d922SBartosz Golaszewski 55573b0d922SBartosz Golaszewski regmap = devm_regmap_init_i2c(dummy_client, regmap_config); 556e7308628SBartosz Golaszewski if (IS_ERR(regmap)) 55773b0d922SBartosz Golaszewski return PTR_ERR(regmap); 55873b0d922SBartosz Golaszewski 55973b0d922SBartosz Golaszewski at24->client[index].client = dummy_client; 56073b0d922SBartosz Golaszewski at24->client[index].regmap = regmap; 56173b0d922SBartosz Golaszewski 56273b0d922SBartosz Golaszewski return 0; 56373b0d922SBartosz Golaszewski } 56473b0d922SBartosz Golaszewski 5654bb5c13cSHeiner Kallweit static unsigned int at24_get_offset_adj(u8 flags, unsigned int byte_len) 5664bb5c13cSHeiner Kallweit { 5674bb5c13cSHeiner Kallweit if (flags & AT24_FLAG_MAC) { 5684bb5c13cSHeiner Kallweit /* EUI-48 starts from 0x9a, EUI-64 from 0x98 */ 5694bb5c13cSHeiner Kallweit return 0xa0 - byte_len; 5704bb5c13cSHeiner Kallweit } else if (flags & AT24_FLAG_SERIAL && flags & AT24_FLAG_ADDR16) { 5714bb5c13cSHeiner Kallweit /* 5724bb5c13cSHeiner Kallweit * For 16 bit address pointers, the word address must contain 5734bb5c13cSHeiner Kallweit * a '10' sequence in bits 11 and 10 regardless of the 5744bb5c13cSHeiner Kallweit * intended position of the address pointer. 5754bb5c13cSHeiner Kallweit */ 5764bb5c13cSHeiner Kallweit return 0x0800; 5774bb5c13cSHeiner Kallweit } else if (flags & AT24_FLAG_SERIAL) { 5784bb5c13cSHeiner Kallweit /* 5794bb5c13cSHeiner Kallweit * Otherwise the word address must begin with a '10' sequence, 5804bb5c13cSHeiner Kallweit * regardless of the intended address. 5814bb5c13cSHeiner Kallweit */ 5824bb5c13cSHeiner Kallweit return 0x0080; 5834bb5c13cSHeiner Kallweit } else { 5844bb5c13cSHeiner Kallweit return 0; 5854bb5c13cSHeiner Kallweit } 5864bb5c13cSHeiner Kallweit } 5874bb5c13cSHeiner Kallweit 58848b6a7d1SBartosz Golaszewski static int at24_probe(struct i2c_client *client) 5895195e509SWolfram Sang { 590eef69398SBartosz Golaszewski struct regmap_config regmap_config = { }; 5918cdc4e7eSBartosz Golaszewski struct nvmem_config nvmem_config = { }; 5924fa882c9SBartosz Golaszewski u32 byte_len, page_size, flags, addrw; 5934fa882c9SBartosz Golaszewski const struct at24_chip_data *cdata; 594021c7d7bSBartosz Golaszewski struct device *dev = &client->dev; 59534d43fafSBartosz Golaszewski bool i2c_fn_i2c, i2c_fn_block; 5965ca2b5b7SBartosz Golaszewski unsigned int i, num_addresses; 5975ca2b5b7SBartosz Golaszewski struct at24_data *at24; 598*1e96078eSSakari Ailus bool full_power; 599551a1266SBartosz Golaszewski struct regmap *regmap; 6005ca2b5b7SBartosz Golaszewski bool writable; 60100f0ea70SBartosz Golaszewski u8 test_byte; 6025ca2b5b7SBartosz Golaszewski int err; 6035195e509SWolfram Sang 60434d43fafSBartosz Golaszewski i2c_fn_i2c = i2c_check_functionality(client->adapter, I2C_FUNC_I2C); 60534d43fafSBartosz Golaszewski i2c_fn_block = i2c_check_functionality(client->adapter, 60634d43fafSBartosz Golaszewski I2C_FUNC_SMBUS_WRITE_I2C_BLOCK); 60734d43fafSBartosz Golaszewski 6084fa882c9SBartosz Golaszewski cdata = at24_get_chip_data(dev); 6094fa882c9SBartosz Golaszewski if (IS_ERR(cdata)) 6104fa882c9SBartosz Golaszewski return PTR_ERR(cdata); 6114fa882c9SBartosz Golaszewski 6124fa882c9SBartosz Golaszewski err = device_property_read_u32(dev, "pagesize", &page_size); 613feb2f19bSBartosz Golaszewski if (err) 6144fa882c9SBartosz Golaszewski /* 6154fa882c9SBartosz Golaszewski * This is slow, but we can't know all eeproms, so we better 616dce91ba3SBartosz Golaszewski * play safe. Specifying custom eeprom-types via device tree 617dce91ba3SBartosz Golaszewski * or properties is recommended anyhow. 6184fa882c9SBartosz Golaszewski */ 6194fa882c9SBartosz Golaszewski page_size = 1; 6204fa882c9SBartosz Golaszewski 6214fa882c9SBartosz Golaszewski flags = cdata->flags; 6224fa882c9SBartosz Golaszewski if (device_property_present(dev, "read-only")) 6234fa882c9SBartosz Golaszewski flags |= AT24_FLAG_READONLY; 6244fa882c9SBartosz Golaszewski if (device_property_present(dev, "no-read-rollover")) 6254fa882c9SBartosz Golaszewski flags |= AT24_FLAG_NO_RDROL; 6264fa882c9SBartosz Golaszewski 6274fa882c9SBartosz Golaszewski err = device_property_read_u32(dev, "address-width", &addrw); 6284fa882c9SBartosz Golaszewski if (!err) { 6294fa882c9SBartosz Golaszewski switch (addrw) { 6304fa882c9SBartosz Golaszewski case 8: 6314fa882c9SBartosz Golaszewski if (flags & AT24_FLAG_ADDR16) 6324fa882c9SBartosz Golaszewski dev_warn(dev, 6334fa882c9SBartosz Golaszewski "Override address width to be 8, while default is 16\n"); 6344fa882c9SBartosz Golaszewski flags &= ~AT24_FLAG_ADDR16; 6354fa882c9SBartosz Golaszewski break; 6364fa882c9SBartosz Golaszewski case 16: 6374fa882c9SBartosz Golaszewski flags |= AT24_FLAG_ADDR16; 6384fa882c9SBartosz Golaszewski break; 6394fa882c9SBartosz Golaszewski default: 6404fa882c9SBartosz Golaszewski dev_warn(dev, "Bad \"address-width\" property: %u\n", 6414fa882c9SBartosz Golaszewski addrw); 6424fa882c9SBartosz Golaszewski } 6434fa882c9SBartosz Golaszewski } 6444fa882c9SBartosz Golaszewski 6454fa882c9SBartosz Golaszewski err = device_property_read_u32(dev, "size", &byte_len); 6464fa882c9SBartosz Golaszewski if (err) 6474fa882c9SBartosz Golaszewski byte_len = cdata->byte_len; 6485195e509SWolfram Sang 64934d43fafSBartosz Golaszewski if (!i2c_fn_i2c && !i2c_fn_block) 6504fa882c9SBartosz Golaszewski page_size = 1; 651551a1266SBartosz Golaszewski 6524fa882c9SBartosz Golaszewski if (!page_size) { 653021c7d7bSBartosz Golaszewski dev_err(dev, "page_size must not be 0!\n"); 654f0ac2363SNikolay Balandin return -EINVAL; 65545efe847SWolfram Sang } 656de5db101SBartosz Golaszewski 6574fa882c9SBartosz Golaszewski if (!is_power_of_2(page_size)) 658021c7d7bSBartosz Golaszewski dev_warn(dev, "page_size looks suspicious (no power of 2)!\n"); 6595195e509SWolfram Sang 660950bcbbeSBartosz Golaszewski err = device_property_read_u32(dev, "num-addresses", &num_addresses); 661950bcbbeSBartosz Golaszewski if (err) { 6624fa882c9SBartosz Golaszewski if (flags & AT24_FLAG_TAKE8ADDR) 6635195e509SWolfram Sang num_addresses = 8; 6645195e509SWolfram Sang else 6654fa882c9SBartosz Golaszewski num_addresses = DIV_ROUND_UP(byte_len, 6664fa882c9SBartosz Golaszewski (flags & AT24_FLAG_ADDR16) ? 65536 : 256); 667950bcbbeSBartosz Golaszewski } 6685195e509SWolfram Sang 6694fa882c9SBartosz Golaszewski if ((flags & AT24_FLAG_SERIAL) && (flags & AT24_FLAG_MAC)) { 670551a1266SBartosz Golaszewski dev_err(dev, 671551a1266SBartosz Golaszewski "invalid device data - cannot have both AT24_FLAG_SERIAL & AT24_FLAG_MAC."); 672551a1266SBartosz Golaszewski return -EINVAL; 673551a1266SBartosz Golaszewski } 674551a1266SBartosz Golaszewski 675eef69398SBartosz Golaszewski regmap_config.val_bits = 8; 6764fa882c9SBartosz Golaszewski regmap_config.reg_bits = (flags & AT24_FLAG_ADDR16) ? 16 : 8; 677d154316dSBartosz Golaszewski regmap_config.disable_locking = true; 6785c015258SHeiner Kallweit 679551a1266SBartosz Golaszewski regmap = devm_regmap_init_i2c(client, ®map_config); 680551a1266SBartosz Golaszewski if (IS_ERR(regmap)) 681551a1266SBartosz Golaszewski return PTR_ERR(regmap); 682551a1266SBartosz Golaszewski 6839ae9d9bfSGustavo A. R. Silva at24 = devm_kzalloc(dev, struct_size(at24, client, num_addresses), 6849ae9d9bfSGustavo A. R. Silva GFP_KERNEL); 685f0ac2363SNikolay Balandin if (!at24) 686f0ac2363SNikolay Balandin return -ENOMEM; 6875195e509SWolfram Sang 6885195e509SWolfram Sang mutex_init(&at24->lock); 6894fa882c9SBartosz Golaszewski at24->byte_len = byte_len; 6904fa882c9SBartosz Golaszewski at24->page_size = page_size; 6914fa882c9SBartosz Golaszewski at24->flags = flags; 692a4423cedSJean Delvare at24->read_post = cdata->read_post; 6935195e509SWolfram Sang at24->num_addresses = num_addresses; 6944fa882c9SBartosz Golaszewski at24->offset_adj = at24_get_offset_adj(flags, byte_len); 695551a1266SBartosz Golaszewski at24->client[0].client = client; 696551a1266SBartosz Golaszewski at24->client[0].regmap = regmap; 6975195e509SWolfram Sang 698cd5676dbSBibby Hsieh at24->vcc_reg = devm_regulator_get(dev, "vcc"); 699cd5676dbSBibby Hsieh if (IS_ERR(at24->vcc_reg)) 700cd5676dbSBibby Hsieh return PTR_ERR(at24->vcc_reg); 7016ce261e8SBartosz Golaszewski 7024fa882c9SBartosz Golaszewski writable = !(flags & AT24_FLAG_READONLY); 7035195e509SWolfram Sang if (writable) { 704ec3c2d51SBartosz Golaszewski at24->write_max = min_t(unsigned int, 7054fa882c9SBartosz Golaszewski page_size, at24_io_limit); 70634d43fafSBartosz Golaszewski if (!i2c_fn_i2c && at24->write_max > I2C_SMBUS_BLOCK_MAX) 707a23727cbSHeiner Kallweit at24->write_max = I2C_SMBUS_BLOCK_MAX; 7085195e509SWolfram Sang } 7095195e509SWolfram Sang 7105195e509SWolfram Sang /* use dummy devices for multiple-address chips */ 7115195e509SWolfram Sang for (i = 1; i < num_addresses; i++) { 71273b0d922SBartosz Golaszewski err = at24_make_dummy_client(at24, i, ®map_config); 713e7308628SBartosz Golaszewski if (err) 71473b0d922SBartosz Golaszewski return err; 7155c015258SHeiner Kallweit } 7165195e509SWolfram Sang 71761f764c3SJon Hunter /* 718c36748acSJérôme Glisse * We initialize nvmem_config.id to NVMEM_DEVID_AUTO even if the 719c36748acSJérôme Glisse * label property is set as some platform can have multiple eeproms 720c36748acSJérôme Glisse * with same label and we can not register each of those with same 721c36748acSJérôme Glisse * label. Failing to register those eeproms trigger cascade failure 722c36748acSJérôme Glisse * on such platform. 72361f764c3SJon Hunter */ 724c36748acSJérôme Glisse nvmem_config.id = NVMEM_DEVID_AUTO; 725c36748acSJérôme Glisse 72661f764c3SJon Hunter if (device_property_present(dev, "label")) { 72761f764c3SJon Hunter err = device_property_read_string(dev, "label", 72861f764c3SJon Hunter &nvmem_config.name); 72961f764c3SJon Hunter if (err) 73061f764c3SJon Hunter return err; 73161f764c3SJon Hunter } else { 732021c7d7bSBartosz Golaszewski nvmem_config.name = dev_name(dev); 73361f764c3SJon Hunter } 73461f764c3SJon Hunter 73561f764c3SJon Hunter nvmem_config.type = NVMEM_TYPE_EEPROM; 736021c7d7bSBartosz Golaszewski nvmem_config.dev = dev; 7378cdc4e7eSBartosz Golaszewski nvmem_config.read_only = !writable; 73825e5ef30SJean Delvare nvmem_config.root_only = !(flags & AT24_FLAG_IRUGO); 7398cdc4e7eSBartosz Golaszewski nvmem_config.owner = THIS_MODULE; 7408cdc4e7eSBartosz Golaszewski nvmem_config.compat = true; 741021c7d7bSBartosz Golaszewski nvmem_config.base_dev = dev; 7428cdc4e7eSBartosz Golaszewski nvmem_config.reg_read = at24_read; 7438cdc4e7eSBartosz Golaszewski nvmem_config.reg_write = at24_write; 7448cdc4e7eSBartosz Golaszewski nvmem_config.priv = at24; 7458cdc4e7eSBartosz Golaszewski nvmem_config.stride = 1; 7468cdc4e7eSBartosz Golaszewski nvmem_config.word_size = 1; 7474fa882c9SBartosz Golaszewski nvmem_config.size = byte_len; 74857d15550SAndrew Lunn 749b20eb4c1SBartosz Golaszewski i2c_set_clientdata(client, at24); 750b20eb4c1SBartosz Golaszewski 751*1e96078eSSakari Ailus full_power = acpi_dev_state_d0(&client->dev); 752*1e96078eSSakari Ailus if (full_power) { 753cd5676dbSBibby Hsieh err = regulator_enable(at24->vcc_reg); 754cd5676dbSBibby Hsieh if (err) { 755cd5676dbSBibby Hsieh dev_err(dev, "Failed to enable vcc regulator\n"); 756cd5676dbSBibby Hsieh return err; 757cd5676dbSBibby Hsieh } 758cd5676dbSBibby Hsieh 759b20eb4c1SBartosz Golaszewski pm_runtime_set_active(dev); 760*1e96078eSSakari Ailus } 761b20eb4c1SBartosz Golaszewski pm_runtime_enable(dev); 762b20eb4c1SBartosz Golaszewski 76345df80d7SVadym Kochan at24->nvmem = devm_nvmem_register(dev, &nvmem_config); 76445df80d7SVadym Kochan if (IS_ERR(at24->nvmem)) { 76545df80d7SVadym Kochan pm_runtime_disable(dev); 7662962484dSHsin-Yi Wang if (!pm_runtime_status_suspended(dev)) 76745df80d7SVadym Kochan regulator_disable(at24->vcc_reg); 76845df80d7SVadym Kochan return PTR_ERR(at24->nvmem); 76945df80d7SVadym Kochan } 77045df80d7SVadym Kochan 771b20eb4c1SBartosz Golaszewski /* 772*1e96078eSSakari Ailus * Perform a one-byte test read to verify that the chip is functional, 773*1e96078eSSakari Ailus * unless powering on the device is to be avoided during probe (i.e. 774*1e96078eSSakari Ailus * it's powered off right now). 775b20eb4c1SBartosz Golaszewski */ 776*1e96078eSSakari Ailus if (full_power) { 777b20eb4c1SBartosz Golaszewski err = at24_read(at24, 0, &test_byte, 1); 778b20eb4c1SBartosz Golaszewski if (err) { 779b20eb4c1SBartosz Golaszewski pm_runtime_disable(dev); 7802962484dSHsin-Yi Wang if (!pm_runtime_status_suspended(dev)) 781cd5676dbSBibby Hsieh regulator_disable(at24->vcc_reg); 782b20eb4c1SBartosz Golaszewski return -ENODEV; 78357d15550SAndrew Lunn } 784*1e96078eSSakari Ailus } 7855195e509SWolfram Sang 78658d6fee5SMichael Auchter pm_runtime_idle(dev); 78758d6fee5SMichael Auchter 788285be87cSJean Delvare if (writable) 789285be87cSJean Delvare dev_info(dev, "%u byte %s EEPROM, writable, %u bytes/write\n", 790285be87cSJean Delvare byte_len, client->name, at24->write_max); 791285be87cSJean Delvare else 792285be87cSJean Delvare dev_info(dev, "%u byte %s EEPROM, read-only\n", 793285be87cSJean Delvare byte_len, client->name); 7945195e509SWolfram Sang 7955195e509SWolfram Sang return 0; 7965195e509SWolfram Sang } 7975195e509SWolfram Sang 798486a5c28SBill Pemberton static int at24_remove(struct i2c_client *client) 7995195e509SWolfram Sang { 800cd5676dbSBibby Hsieh struct at24_data *at24 = i2c_get_clientdata(client); 801cd5676dbSBibby Hsieh 80298e82010SDivagar Mohandass pm_runtime_disable(&client->dev); 803*1e96078eSSakari Ailus if (acpi_dev_state_d0(&client->dev)) { 804cd5676dbSBibby Hsieh if (!pm_runtime_status_suspended(&client->dev)) 805cd5676dbSBibby Hsieh regulator_disable(at24->vcc_reg); 80698e82010SDivagar Mohandass pm_runtime_set_suspended(&client->dev); 807*1e96078eSSakari Ailus } 80898e82010SDivagar Mohandass 8095195e509SWolfram Sang return 0; 8105195e509SWolfram Sang } 8115195e509SWolfram Sang 812cd5676dbSBibby Hsieh static int __maybe_unused at24_suspend(struct device *dev) 813cd5676dbSBibby Hsieh { 814cd5676dbSBibby Hsieh struct i2c_client *client = to_i2c_client(dev); 815cd5676dbSBibby Hsieh struct at24_data *at24 = i2c_get_clientdata(client); 816cd5676dbSBibby Hsieh 817cd5676dbSBibby Hsieh return regulator_disable(at24->vcc_reg); 818cd5676dbSBibby Hsieh } 819cd5676dbSBibby Hsieh 820cd5676dbSBibby Hsieh static int __maybe_unused at24_resume(struct device *dev) 821cd5676dbSBibby Hsieh { 822cd5676dbSBibby Hsieh struct i2c_client *client = to_i2c_client(dev); 823cd5676dbSBibby Hsieh struct at24_data *at24 = i2c_get_clientdata(client); 824cd5676dbSBibby Hsieh 825cd5676dbSBibby Hsieh return regulator_enable(at24->vcc_reg); 826cd5676dbSBibby Hsieh } 827cd5676dbSBibby Hsieh 828cd5676dbSBibby Hsieh static const struct dev_pm_ops at24_pm_ops = { 829cd5676dbSBibby Hsieh SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 830cd5676dbSBibby Hsieh pm_runtime_force_resume) 831cd5676dbSBibby Hsieh SET_RUNTIME_PM_OPS(at24_suspend, at24_resume, NULL) 832cd5676dbSBibby Hsieh }; 833cd5676dbSBibby Hsieh 8345195e509SWolfram Sang static struct i2c_driver at24_driver = { 8355195e509SWolfram Sang .driver = { 8365195e509SWolfram Sang .name = "at24", 837cd5676dbSBibby Hsieh .pm = &at24_pm_ops, 8387f2a2f0dSJavier Martinez Canillas .of_match_table = at24_of_match, 83940d8edc9SAndy Shevchenko .acpi_match_table = ACPI_PTR(at24_acpi_ids), 8405195e509SWolfram Sang }, 84148b6a7d1SBartosz Golaszewski .probe_new = at24_probe, 8422d6bed9cSBill Pemberton .remove = at24_remove, 8435195e509SWolfram Sang .id_table = at24_ids, 844*1e96078eSSakari Ailus .flags = I2C_DRV_ACPI_WAIVE_D0_PROBE, 8455195e509SWolfram Sang }; 8465195e509SWolfram Sang 8475195e509SWolfram Sang static int __init at24_init(void) 8485195e509SWolfram Sang { 849ec3c2d51SBartosz Golaszewski if (!at24_io_limit) { 850ec3c2d51SBartosz Golaszewski pr_err("at24: at24_io_limit must not be 0!\n"); 85145efe847SWolfram Sang return -EINVAL; 85245efe847SWolfram Sang } 85345efe847SWolfram Sang 854ec3c2d51SBartosz Golaszewski at24_io_limit = rounddown_pow_of_two(at24_io_limit); 8555195e509SWolfram Sang return i2c_add_driver(&at24_driver); 8565195e509SWolfram Sang } 8575195e509SWolfram Sang module_init(at24_init); 8585195e509SWolfram Sang 8595195e509SWolfram Sang static void __exit at24_exit(void) 8605195e509SWolfram Sang { 8615195e509SWolfram Sang i2c_del_driver(&at24_driver); 8625195e509SWolfram Sang } 8635195e509SWolfram Sang module_exit(at24_exit); 8645195e509SWolfram Sang 8655195e509SWolfram Sang MODULE_DESCRIPTION("Driver for most I2C EEPROMs"); 8665195e509SWolfram Sang MODULE_AUTHOR("David Brownell and Wolfram Sang"); 8675195e509SWolfram Sang MODULE_LICENSE("GPL"); 868