[PATCH v4 6/7] mtd: spi-nor: Use the spi_mem_xx() API
Frieder Schrempf
frieder.schrempf at exceet.de
Thu May 3 11:40:41 PDT 2018
On 26.04.2018 18:18, Boris Brezillon wrote:
> The spi_mem_xxx() API has been introduced to replace the
> spi_flash_read() one. Make use of it so we can get rid of
> spi_flash_read().
>
> Note that using spi_mem_xx() also simplifies the code because this API
> takes care of using the regular spi_sync() interface when the optimized
> ->mem_ops interface is not implemented by the controller.
>
> Signed-off-by: Boris Brezillon <boris.brezillon at bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf at exceet.de>
Tested-by: Frieder Schrempf <frieder.schrempf at exceet.de>
Regards,
Frieder
> ---
> Changes in v4:
> - none
>
> Changes in v3:
> - none
>
> Changes in v2:
> - include spi-mem.h
> - treat op->addr.val differently since it's now an u64
> - Replace SPI_MEM_OP_DATA_OUT() by SPI_MEM_OP_DATA_IN() in m25p80_read()
> ---
> drivers/mtd/devices/Kconfig | 1 +
> drivers/mtd/devices/m25p80.c | 236 +++++++++++++++----------------------------
> 2 files changed, 80 insertions(+), 157 deletions(-)
>
> diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig
> index 6def5445e03e..57b02c4b3f63 100644
> --- a/drivers/mtd/devices/Kconfig
> +++ b/drivers/mtd/devices/Kconfig
> @@ -81,6 +81,7 @@ config MTD_DATAFLASH_OTP
> config MTD_M25P80
> tristate "Support most SPI Flash chips (AT26DF, M25P, W25X, ...)"
> depends on SPI_MASTER && MTD_SPI_NOR
> + select SPI_MEM
> help
> This enables access to most modern SPI flash chips, used for
> program and data storage. Series supported include Atmel AT26DF,
> diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
> index a4e18f6aaa33..3dc022d3b53e 100644
> --- a/drivers/mtd/devices/m25p80.c
> +++ b/drivers/mtd/devices/m25p80.c
> @@ -24,12 +24,13 @@
> #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>
>
> #define MAX_CMD_SIZE 6
> struct m25p {
> - struct spi_device *spi;
> + struct spi_mem *spimem;
> struct spi_nor spi_nor;
> u8 command[MAX_CMD_SIZE];
> };
> @@ -37,97 +38,68 @@ struct m25p {
> static int m25p80_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len)
> {
> struct m25p *flash = nor->priv;
> - struct spi_device *spi = flash->spi;
> + 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, val, 1));
> int ret;
>
> - ret = spi_write_then_read(spi, &code, 1, val, len);
> + ret = spi_mem_exec_op(flash->spimem, &op);
> if (ret < 0)
> - dev_err(&spi->dev, "error %d reading %x\n", ret, code);
> + dev_err(&flash->spimem->spi->dev, "error %d reading %x\n", ret,
> + code);
>
> return ret;
> }
>
> -static void m25p_addr2cmd(struct spi_nor *nor, unsigned int addr, u8 *cmd)
> -{
> - /* opcode is in cmd[0] */
> - cmd[1] = addr >> (nor->addr_width * 8 - 8);
> - cmd[2] = addr >> (nor->addr_width * 8 - 16);
> - cmd[3] = addr >> (nor->addr_width * 8 - 24);
> - cmd[4] = addr >> (nor->addr_width * 8 - 32);
> -}
> -
> -static int m25p_cmdsz(struct spi_nor *nor)
> -{
> - return 1 + nor->addr_width;
> -}
> -
> static int m25p80_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
> {
> struct m25p *flash = nor->priv;
> - struct spi_device *spi = flash->spi;
> -
> - flash->command[0] = opcode;
> - if (buf)
> - memcpy(&flash->command[1], buf, len);
> + 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, buf, 1));
>
> - return spi_write(spi, flash->command, len + 1);
> + return spi_mem_exec_op(flash->spimem, &op);
> }
>
> 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_device *spi = flash->spi;
> - unsigned int inst_nbits, addr_nbits, data_nbits, data_idx;
> - struct spi_transfer t[3] = {};
> - struct spi_message m;
> - int cmd_sz = m25p_cmdsz(nor);
> - ssize_t ret;
> + 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_DUMMY(0, 1),
> + SPI_MEM_OP_DATA_OUT(len, buf, 1));
> + size_t remaining = len;
> + int ret;
>
> /* get transfer protocols. */
> - inst_nbits = spi_nor_get_protocol_inst_nbits(nor->write_proto);
> - addr_nbits = spi_nor_get_protocol_addr_nbits(nor->write_proto);
> - data_nbits = spi_nor_get_protocol_data_nbits(nor->write_proto);
> -
> - spi_message_init(&m);
> + 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.dummy.buswidth = op.addr.buswidth;
> + op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
>
> if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
> - cmd_sz = 1;
> -
> - flash->command[0] = nor->program_opcode;
> - m25p_addr2cmd(nor, to, flash->command);
> + op.addr.nbytes = 0;
>
> - t[0].tx_buf = flash->command;
> - t[0].tx_nbits = inst_nbits;
> - t[0].len = cmd_sz;
> - spi_message_add_tail(&t[0], &m);
> -
> - /* split the op code and address bytes into two transfers if needed. */
> - data_idx = 1;
> - if (addr_nbits != inst_nbits) {
> - t[0].len = 1;
> + while (remaining) {
> + op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX;
> + ret = spi_mem_adjust_op_size(flash->spimem, &op);
> + if (ret)
> + return ret;
>
> - t[1].tx_buf = &flash->command[1];
> - t[1].tx_nbits = addr_nbits;
> - t[1].len = cmd_sz - 1;
> - spi_message_add_tail(&t[1], &m);
> + ret = spi_mem_exec_op(flash->spimem, &op);
> + if (ret)
> + return ret;
>
> - data_idx = 2;
> + op.addr.val += op.data.nbytes;
> + remaining -= op.data.nbytes;
> + op.data.buf.out += op.data.nbytes;
> }
>
> - t[data_idx].tx_buf = buf;
> - t[data_idx].tx_nbits = data_nbits;
> - t[data_idx].len = len;
> - spi_message_add_tail(&t[data_idx], &m);
> -
> - ret = spi_sync(spi, &m);
> - if (ret)
> - return ret;
> -
> - ret = m.actual_length - cmd_sz;
> - if (ret < 0)
> - return -EIO;
> - return ret;
> + return len;
> }
>
> /*
> @@ -138,92 +110,39 @@ 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_device *spi = flash->spi;
> - unsigned int inst_nbits, addr_nbits, data_nbits, data_idx;
> - struct spi_transfer t[3];
> - struct spi_message m;
> - unsigned int dummy = nor->read_dummy;
> - ssize_t ret;
> - int cmd_sz;
> + 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. */
> - inst_nbits = spi_nor_get_protocol_inst_nbits(nor->read_proto);
> - addr_nbits = spi_nor_get_protocol_addr_nbits(nor->read_proto);
> - data_nbits = spi_nor_get_protocol_data_nbits(nor->read_proto);
> + 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 */
> - dummy = (dummy * addr_nbits) / 8;
> -
> - if (spi_flash_read_supported(spi)) {
> - struct spi_flash_read_message msg;
> -
> - memset(&msg, 0, sizeof(msg));
> + op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
>
> - msg.buf = buf;
> - msg.from = from;
> - msg.len = len;
> - msg.read_opcode = nor->read_opcode;
> - msg.addr_width = nor->addr_width;
> - msg.dummy_bytes = dummy;
> - msg.opcode_nbits = inst_nbits;
> - msg.addr_nbits = addr_nbits;
> - msg.data_nbits = data_nbits;
> -
> - ret = spi_flash_read(spi, &msg);
> - if (ret < 0)
> + while (remaining) {
> + op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX;
> + ret = spi_mem_adjust_op_size(flash->spimem, &op);
> + if (ret)
> return ret;
> - return msg.retlen;
> - }
>
> - spi_message_init(&m);
> - memset(t, 0, (sizeof t));
> -
> - flash->command[0] = nor->read_opcode;
> - m25p_addr2cmd(nor, from, flash->command);
> -
> - t[0].tx_buf = flash->command;
> - t[0].tx_nbits = inst_nbits;
> - t[0].len = m25p_cmdsz(nor) + dummy;
> - spi_message_add_tail(&t[0], &m);
> -
> - /*
> - * Set all dummy/mode cycle bits to avoid sending some manufacturer
> - * specific pattern, which might make the memory enter its Continuous
> - * Read mode by mistake.
> - * Based on the different mode cycle bit patterns listed and described
> - * in the JESD216B specification, the 0xff value works for all memories
> - * and all manufacturers.
> - */
> - cmd_sz = t[0].len;
> - memset(flash->command + cmd_sz - dummy, 0xff, dummy);
> -
> - /* split the op code and address bytes into two transfers if needed. */
> - data_idx = 1;
> - if (addr_nbits != inst_nbits) {
> - t[0].len = 1;
> -
> - t[1].tx_buf = &flash->command[1];
> - t[1].tx_nbits = addr_nbits;
> - t[1].len = cmd_sz - 1;
> - spi_message_add_tail(&t[1], &m);
> + ret = spi_mem_exec_op(flash->spimem, &op);
> + if (ret)
> + return ret;
>
> - data_idx = 2;
> + op.addr.val += op.data.nbytes;
> + remaining -= op.data.nbytes;
> + op.data.buf.in += op.data.nbytes;
> }
>
> - t[data_idx].rx_buf = buf;
> - t[data_idx].rx_nbits = data_nbits;
> - t[data_idx].len = min3(len, spi_max_transfer_size(spi),
> - spi_max_message_size(spi) - cmd_sz);
> - spi_message_add_tail(&t[data_idx], &m);
> -
> - ret = spi_sync(spi, &m);
> - if (ret)
> - return ret;
> -
> - ret = m.actual_length - cmd_sz;
> - if (ret < 0)
> - return -EIO;
> - return ret;
> + return len;
> }
>
> /*
> @@ -231,8 +150,9 @@ static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
> * 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_device *spi)
> +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;
> @@ -244,9 +164,9 @@ static int m25p_probe(struct spi_device *spi)
> char *flash_name;
> int ret;
>
> - data = dev_get_platdata(&spi->dev);
> + data = dev_get_platdata(&spimem->spi->dev);
>
> - flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL);
> + flash = devm_kzalloc(&spimem->spi->dev, sizeof(*flash), GFP_KERNEL);
> if (!flash)
> return -ENOMEM;
>
> @@ -258,12 +178,12 @@ static int m25p_probe(struct spi_device *spi)
> nor->write_reg = m25p80_write_reg;
> nor->read_reg = m25p80_read_reg;
>
> - nor->dev = &spi->dev;
> + nor->dev = &spimem->spi->dev;
> spi_nor_set_flash_node(nor, spi->dev.of_node);
> nor->priv = flash;
>
> spi_set_drvdata(spi, flash);
> - flash->spi = spi;
> + flash->spimem = spimem;
>
> if (spi->mode & SPI_RX_QUAD) {
> hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
> @@ -303,9 +223,9 @@ static int m25p_probe(struct spi_device *spi)
> }
>
>
> -static int m25p_remove(struct spi_device *spi)
> +static int m25p_remove(struct spi_mem *spimem)
> {
> - struct m25p *flash = spi_get_drvdata(spi);
> + struct m25p *flash = spi_mem_get_drvdata(spimem);
>
> spi_nor_restore(&flash->spi_nor);
>
> @@ -313,9 +233,9 @@ static int m25p_remove(struct spi_device *spi)
> return mtd_device_unregister(&flash->spi_nor.mtd);
> }
>
> -static void m25p_shutdown(struct spi_device *spi)
> +static void m25p_shutdown(struct spi_mem *spimem)
> {
> - struct m25p *flash = spi_get_drvdata(spi);
> + struct m25p *flash = spi_mem_get_drvdata(spimem);
>
> spi_nor_restore(&flash->spi_nor);
> }
> @@ -386,12 +306,14 @@ static const struct of_device_id m25p_of_table[] = {
> };
> MODULE_DEVICE_TABLE(of, m25p_of_table);
>
> -static struct spi_driver m25p80_driver = {
> - .driver = {
> - .name = "m25p80",
> - .of_match_table = m25p_of_table,
> +static struct spi_mem_driver m25p80_driver = {
> + .spidrv = {
> + .driver = {
> + .name = "m25p80",
> + .of_match_table = m25p_of_table,
> + },
> + .id_table = m25p_ids,
> },
> - .id_table = m25p_ids,
> .probe = m25p_probe,
> .remove = m25p_remove,
> .shutdown = m25p_shutdown,
> @@ -402,7 +324,7 @@ static struct spi_driver m25p80_driver = {
> */
> };
>
> -module_spi_driver(m25p80_driver);
> +module_spi_mem_driver(m25p80_driver);
>
> MODULE_LICENSE("GPL");
> MODULE_AUTHOR("Mike Lavender");
>
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