From 12ad2be9d1db3dcce08f29bdc5415db3af58fa60 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Mon, 24 Sep 2012 03:39:39 +0200 Subject: mtd: m25p80: Make fast read configurable via DT Add DT property "m25p,fast-read" that signalises the particular chip supports "fast read" opcode. Signed-off-by: Marek Vasut Signed-off-by: Artem Bityutskiy --- drivers/mtd/devices/m25p80.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) (limited to 'drivers/mtd/devices') diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index 03838bab1f5..82f977456b8 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -73,14 +73,6 @@ #define MAX_READY_WAIT_JIFFIES (40 * HZ) /* M25P16 specs 40s max chip erase */ #define MAX_CMD_SIZE 5 -#ifdef CONFIG_M25PXX_USE_FAST_READ -#define OPCODE_READ OPCODE_FAST_READ -#define FAST_READ_DUMMY_BYTE 1 -#else -#define OPCODE_READ OPCODE_NORM_READ -#define FAST_READ_DUMMY_BYTE 0 -#endif - #define JEDEC_MFR(_jedec_id) ((_jedec_id) >> 16) /****************************************************************************/ @@ -93,6 +85,7 @@ struct m25p { u16 addr_width; u8 erase_opcode; u8 *command; + bool fast_read; }; static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd) @@ -342,6 +335,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, struct m25p *flash = mtd_to_m25p(mtd); struct spi_transfer t[2]; struct spi_message m; + uint8_t opcode; pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev), __func__, (u32)from, len); @@ -354,7 +348,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, * Should add 1 byte DUMMY_BYTE. */ t[0].tx_buf = flash->command; - t[0].len = m25p_cmdsz(flash) + FAST_READ_DUMMY_BYTE; + t[0].len = m25p_cmdsz(flash) + (flash->fast_read ? 1 : 0); spi_message_add_tail(&t[0], &m); t[1].rx_buf = buf; @@ -376,12 +370,14 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, */ /* Set up the write data buffer. */ - flash->command[0] = OPCODE_READ; + opcode = flash->fast_read ? OPCODE_FAST_READ : OPCODE_NORM_READ; + flash->command[0] = opcode; m25p_addr2cmd(flash, from, flash->command); spi_sync(flash->spi, &m); - *retlen = m.actual_length - m25p_cmdsz(flash) - FAST_READ_DUMMY_BYTE; + *retlen = m.actual_length - m25p_cmdsz(flash) - + (flash->fast_read ? 1 : 0); mutex_unlock(&flash->lock); @@ -809,9 +805,10 @@ static int __devinit m25p_probe(struct spi_device *spi) struct flash_info *info; unsigned i; struct mtd_part_parser_data ppdata; + struct device_node __maybe_unused *np = spi->dev.of_node; #ifdef CONFIG_MTD_OF_PARTS - if (!of_device_is_available(spi->dev.of_node)) + if (!of_device_is_available(np)) return -ENODEV; #endif @@ -863,7 +860,8 @@ static int __devinit m25p_probe(struct spi_device *spi) flash = kzalloc(sizeof *flash, GFP_KERNEL); if (!flash) return -ENOMEM; - flash->command = kmalloc(MAX_CMD_SIZE + FAST_READ_DUMMY_BYTE, GFP_KERNEL); + flash->command = kmalloc(MAX_CMD_SIZE + (flash->fast_read ? 1 : 0), + GFP_KERNEL); if (!flash->command) { kfree(flash); return -ENOMEM; @@ -920,6 +918,16 @@ static int __devinit m25p_probe(struct spi_device *spi) flash->page_size = info->page_size; flash->mtd.writebufsize = flash->page_size; + flash->fast_read = false; +#ifdef CONFIG_OF + if (np && of_property_read_bool(np, "m25p,fast-read")) + flash->fast_read = true; +#endif + +#ifdef CONFIG_M25PXX_USE_FAST_READ + flash->fast_read = true; +#endif + if (info->addr_width) flash->addr_width = info->addr_width; else { -- cgit v1.2.3