| /* | 
 |  * MTD SPI driver for ST M25Pxx (and similar) serial flash chips | 
 |  * | 
 |  * Author: Mike Lavender, mike@steroidmicros.com | 
 |  * | 
 |  * Copyright (c) 2005, Intec Automation Inc. | 
 |  * | 
 |  * Some parts are based on lart.c by Abraham Van Der Merwe | 
 |  * | 
 |  * Cleaned up and generalized based on mtd_dataflash.c | 
 |  * | 
 |  * This code 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. | 
 |  * | 
 |  */ | 
 |  | 
 | #include <linux/err.h> | 
 | #include <linux/errno.h> | 
 | #include <linux/module.h> | 
 | #include <linux/device.h> | 
 |  | 
 | #include <linux/mtd/mtd.h> | 
 | #include <linux/mtd/partitions.h> | 
 |  | 
 | #include <linux/spi/spi.h> | 
 | #include <linux/spi/spi-mem.h> | 
 | #include <linux/spi/flash.h> | 
 | #include <linux/mtd/spi-nor.h> | 
 |  | 
 | struct m25p { | 
 | 	struct spi_mem		*spimem; | 
 | 	struct spi_nor		spi_nor; | 
 | }; | 
 |  | 
 | static int m25p80_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len) | 
 | { | 
 | 	struct m25p *flash = nor->priv; | 
 | 	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(code, 1), | 
 | 					  SPI_MEM_OP_NO_ADDR, | 
 | 					  SPI_MEM_OP_NO_DUMMY, | 
 | 					  SPI_MEM_OP_DATA_IN(len, NULL, 1)); | 
 | 	void *scratchbuf; | 
 | 	int ret; | 
 |  | 
 | 	scratchbuf = kmalloc(len, GFP_KERNEL); | 
 | 	if (!scratchbuf) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	op.data.buf.in = scratchbuf; | 
 | 	ret = spi_mem_exec_op(flash->spimem, &op); | 
 | 	if (ret < 0) | 
 | 		dev_err(&flash->spimem->spi->dev, "error %d reading %x\n", ret, | 
 | 			code); | 
 | 	else | 
 | 		memcpy(val, scratchbuf, len); | 
 |  | 
 | 	kfree(scratchbuf); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int m25p80_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) | 
 | { | 
 | 	struct m25p *flash = nor->priv; | 
 | 	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 1), | 
 | 					  SPI_MEM_OP_NO_ADDR, | 
 | 					  SPI_MEM_OP_NO_DUMMY, | 
 | 					  SPI_MEM_OP_DATA_OUT(len, NULL, 1)); | 
 | 	void *scratchbuf; | 
 | 	int ret; | 
 |  | 
 | 	scratchbuf = kmemdup(buf, len, GFP_KERNEL); | 
 | 	if (!scratchbuf) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	op.data.buf.out = scratchbuf; | 
 | 	ret = spi_mem_exec_op(flash->spimem, &op); | 
 | 	kfree(scratchbuf); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len, | 
 | 			    const u_char *buf) | 
 | { | 
 | 	struct m25p *flash = nor->priv; | 
 | 	struct spi_mem_op op = | 
 | 			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 1), | 
 | 				   SPI_MEM_OP_ADDR(nor->addr_width, to, 1), | 
 | 				   SPI_MEM_OP_NO_DUMMY, | 
 | 				   SPI_MEM_OP_DATA_OUT(len, buf, 1)); | 
 | 	int ret; | 
 |  | 
 | 	/* get transfer protocols. */ | 
 | 	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto); | 
 | 	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto); | 
 | 	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto); | 
 |  | 
 | 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second) | 
 | 		op.addr.nbytes = 0; | 
 |  | 
 | 	ret = spi_mem_adjust_op_size(flash->spimem, &op); | 
 | 	if (ret) | 
 | 		return ret; | 
 | 	op.data.nbytes = len < op.data.nbytes ? len : op.data.nbytes; | 
 |  | 
 | 	ret = spi_mem_exec_op(flash->spimem, &op); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	return op.data.nbytes; | 
 | } | 
 |  | 
 | /* | 
 |  * Read an address range from the nor chip.  The address range | 
 |  * may be any size provided it is within the physical boundaries. | 
 |  */ | 
 | static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len, | 
 | 			   u_char *buf) | 
 | { | 
 | 	struct m25p *flash = nor->priv; | 
 | 	struct spi_mem_op op = | 
 | 			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 1), | 
 | 				   SPI_MEM_OP_ADDR(nor->addr_width, from, 1), | 
 | 				   SPI_MEM_OP_DUMMY(nor->read_dummy, 1), | 
 | 				   SPI_MEM_OP_DATA_IN(len, buf, 1)); | 
 | 	size_t remaining = len; | 
 | 	int ret; | 
 |  | 
 | 	/* get transfer protocols. */ | 
 | 	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto); | 
 | 	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto); | 
 | 	op.dummy.buswidth = op.addr.buswidth; | 
 | 	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto); | 
 |  | 
 | 	/* convert the dummy cycles to the number of bytes */ | 
 | 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8; | 
 |  | 
 | 	while (remaining) { | 
 | 		op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX; | 
 | 		ret = spi_mem_adjust_op_size(flash->spimem, &op); | 
 | 		if (ret) | 
 | 			return ret; | 
 |  | 
 | 		ret = spi_mem_exec_op(flash->spimem, &op); | 
 | 		if (ret) | 
 | 			return ret; | 
 |  | 
 | 		op.addr.val += op.data.nbytes; | 
 | 		remaining -= op.data.nbytes; | 
 | 		op.data.buf.in += op.data.nbytes; | 
 | 	} | 
 |  | 
 | 	return len; | 
 | } | 
 |  | 
 | /* | 
 |  * board specific setup should have ensured the SPI clock used here | 
 |  * matches what the READ command supports, at least until this driver | 
 |  * understands FAST_READ (for clocks over 25 MHz). | 
 |  */ | 
 | static int m25p_probe(struct spi_mem *spimem) | 
 | { | 
 | 	struct spi_device *spi = spimem->spi; | 
 | 	struct flash_platform_data	*data; | 
 | 	struct m25p *flash; | 
 | 	struct spi_nor *nor; | 
 | 	struct spi_nor_hwcaps hwcaps = { | 
 | 		.mask = SNOR_HWCAPS_READ | | 
 | 			SNOR_HWCAPS_READ_FAST | | 
 | 			SNOR_HWCAPS_PP, | 
 | 	}; | 
 | 	char *flash_name; | 
 | 	int ret; | 
 |  | 
 | 	data = dev_get_platdata(&spimem->spi->dev); | 
 |  | 
 | 	flash = devm_kzalloc(&spimem->spi->dev, sizeof(*flash), GFP_KERNEL); | 
 | 	if (!flash) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	nor = &flash->spi_nor; | 
 |  | 
 | 	/* install the hooks */ | 
 | 	nor->read = m25p80_read; | 
 | 	nor->write = m25p80_write; | 
 | 	nor->write_reg = m25p80_write_reg; | 
 | 	nor->read_reg = m25p80_read_reg; | 
 |  | 
 | 	nor->dev = &spimem->spi->dev; | 
 | 	spi_nor_set_flash_node(nor, spi->dev.of_node); | 
 | 	nor->priv = flash; | 
 |  | 
 | 	spi_mem_set_drvdata(spimem, flash); | 
 | 	flash->spimem = spimem; | 
 |  | 
 | 	if (spi->mode & SPI_RX_QUAD) { | 
 | 		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4; | 
 |  | 
 | 		if (spi->mode & SPI_TX_QUAD) | 
 | 			hwcaps.mask |= (SNOR_HWCAPS_READ_1_4_4 | | 
 | 					SNOR_HWCAPS_PP_1_1_4 | | 
 | 					SNOR_HWCAPS_PP_1_4_4); | 
 | 	} else if (spi->mode & SPI_RX_DUAL) { | 
 | 		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2; | 
 |  | 
 | 		if (spi->mode & SPI_TX_DUAL) | 
 | 			hwcaps.mask |= SNOR_HWCAPS_READ_1_2_2; | 
 | 	} | 
 |  | 
 | 	if (data && data->name) | 
 | 		nor->mtd.name = data->name; | 
 |  | 
 | 	if (!nor->mtd.name) | 
 | 		nor->mtd.name = spi_mem_get_name(spimem); | 
 |  | 
 | 	/* For some (historical?) reason many platforms provide two different | 
 | 	 * names in flash_platform_data: "name" and "type". Quite often name is | 
 | 	 * set to "m25p80" and then "type" provides a real chip name. | 
 | 	 * If that's the case, respect "type" and ignore a "name". | 
 | 	 */ | 
 | 	if (data && data->type) | 
 | 		flash_name = data->type; | 
 | 	else if (!strcmp(spi->modalias, "spi-nor")) | 
 | 		flash_name = NULL; /* auto-detect */ | 
 | 	else | 
 | 		flash_name = spi->modalias; | 
 |  | 
 | 	ret = spi_nor_scan(nor, flash_name, &hwcaps); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	return mtd_device_register(&nor->mtd, data ? data->parts : NULL, | 
 | 				   data ? data->nr_parts : 0); | 
 | } | 
 |  | 
 |  | 
 | static int m25p_remove(struct spi_mem *spimem) | 
 | { | 
 | 	struct m25p	*flash = spi_mem_get_drvdata(spimem); | 
 |  | 
 | 	spi_nor_restore(&flash->spi_nor); | 
 |  | 
 | 	/* Clean up MTD stuff. */ | 
 | 	return mtd_device_unregister(&flash->spi_nor.mtd); | 
 | } | 
 |  | 
 | static void m25p_shutdown(struct spi_mem *spimem) | 
 | { | 
 | 	struct m25p *flash = spi_mem_get_drvdata(spimem); | 
 |  | 
 | 	spi_nor_restore(&flash->spi_nor); | 
 | } | 
 | /* | 
 |  * Do NOT add to this array without reading the following: | 
 |  * | 
 |  * Historically, many flash devices are bound to this driver by their name. But | 
 |  * since most of these flash are compatible to some extent, and their | 
 |  * differences can often be differentiated by the JEDEC read-ID command, we | 
 |  * encourage new users to add support to the spi-nor library, and simply bind | 
 |  * against a generic string here (e.g., "jedec,spi-nor"). | 
 |  * | 
 |  * Many flash names are kept here in this list (as well as in spi-nor.c) to | 
 |  * keep them available as module aliases for existing platforms. | 
 |  */ | 
 | static const struct spi_device_id m25p_ids[] = { | 
 | 	/* | 
 | 	 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and | 
 | 	 * hack around the fact that the SPI core does not provide uevent | 
 | 	 * matching for .of_match_table | 
 | 	 */ | 
 | 	{"spi-nor"}, | 
 |  | 
 | 	/* | 
 | 	 * Entries not used in DTs that should be safe to drop after replacing | 
 | 	 * them with "spi-nor" in platform data. | 
 | 	 */ | 
 | 	{"s25sl064a"},	{"w25x16"},	{"m25p10"},	{"m25px64"}, | 
 |  | 
 | 	/* | 
 | 	 * Entries that were used in DTs without "jedec,spi-nor" fallback and | 
 | 	 * should be kept for backward compatibility. | 
 | 	 */ | 
 | 	{"at25df321a"},	{"at25df641"},	{"at26df081a"}, | 
 | 	{"mx25l4005a"},	{"mx25l1606e"},	{"mx25l6405d"},	{"mx25l12805d"}, | 
 | 	{"mx25l25635e"},{"mx66l51235l"}, | 
 | 	{"n25q064"},	{"n25q128a11"},	{"n25q128a13"},	{"n25q512a"}, | 
 | 	{"s25fl256s1"},	{"s25fl512s"},	{"s25sl12801"},	{"s25fl008k"}, | 
 | 	{"s25fl064k"}, | 
 | 	{"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"}, | 
 | 	{"m25p40"},	{"m25p80"},	{"m25p16"},	{"m25p32"}, | 
 | 	{"m25p64"},	{"m25p128"}, | 
 | 	{"w25x80"},	{"w25x32"},	{"w25q32"},	{"w25q32dw"}, | 
 | 	{"w25q80bl"},	{"w25q128"},	{"w25q256"}, | 
 |  | 
 | 	/* Flashes that can't be detected using JEDEC */ | 
 | 	{"m25p05-nonjedec"},	{"m25p10-nonjedec"},	{"m25p20-nonjedec"}, | 
 | 	{"m25p40-nonjedec"},	{"m25p80-nonjedec"},	{"m25p16-nonjedec"}, | 
 | 	{"m25p32-nonjedec"},	{"m25p64-nonjedec"},	{"m25p128-nonjedec"}, | 
 |  | 
 | 	/* Everspin MRAMs (non-JEDEC) */ | 
 | 	{ "mr25h128" }, /* 128 Kib, 40 MHz */ | 
 | 	{ "mr25h256" }, /* 256 Kib, 40 MHz */ | 
 | 	{ "mr25h10" },  /*   1 Mib, 40 MHz */ | 
 | 	{ "mr25h40" },  /*   4 Mib, 40 MHz */ | 
 |  | 
 | 	{ }, | 
 | }; | 
 | MODULE_DEVICE_TABLE(spi, m25p_ids); | 
 |  | 
 | static const struct of_device_id m25p_of_table[] = { | 
 | 	/* | 
 | 	 * Generic compatibility for SPI NOR that can be identified by the | 
 | 	 * JEDEC READ ID opcode (0x9F). Use this, if possible. | 
 | 	 */ | 
 | 	{ .compatible = "jedec,spi-nor" }, | 
 | 	{} | 
 | }; | 
 | MODULE_DEVICE_TABLE(of, m25p_of_table); | 
 |  | 
 | static struct spi_mem_driver m25p80_driver = { | 
 | 	.spidrv = { | 
 | 		.driver = { | 
 | 			.name	= "m25p80", | 
 | 			.of_match_table = m25p_of_table, | 
 | 		}, | 
 | 		.id_table	= m25p_ids, | 
 | 	}, | 
 | 	.probe	= m25p_probe, | 
 | 	.remove	= m25p_remove, | 
 | 	.shutdown	= m25p_shutdown, | 
 |  | 
 | 	/* REVISIT: many of these chips have deep power-down modes, which | 
 | 	 * should clearly be entered on suspend() to minimize power use. | 
 | 	 * And also when they're otherwise idle... | 
 | 	 */ | 
 | }; | 
 |  | 
 | module_spi_mem_driver(m25p80_driver); | 
 |  | 
 | MODULE_LICENSE("GPL"); | 
 | MODULE_AUTHOR("Mike Lavender"); | 
 | MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips"); |