From: Geert Uytterhoeven <[email protected]> Add support for accessing the RSPI Data Register using 8-bit operations, based on the SDK reference code. This is needed for RZ/A1H.
The data width is passed using platform data, defaulting to 16-bit for legacy RSPI. QSPI always uses 8-bit accesses. Signed-off-by: Geert Uytterhoeven <[email protected]> --- v2: - Drop last if clause in rspi{write,read}_data(), and document we fall back to 16-bit there - Return sensible error value in rspi_parse_platform_data() - Update copyright header in rspi.h drivers/spi/spi-rspi.c | 89 +++++++++++++++++++++++++++++++++++++++------- include/linux/spi/rspi.h | 4 ++- 2 files changed, 79 insertions(+), 14 deletions(-) diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index 45da760281f9..c3332d2b48e9 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -188,6 +188,8 @@ struct rspi_data { spinlock_t lock; struct clk *clk; u8 spsr; + u8 spdcr; + u8 data_width; int irqs[MAX_NUM_IRQ]; unsigned int num_irqs; const struct spi_ops *ops; @@ -225,8 +227,26 @@ static u16 rspi_read16(const struct rspi_data *rspi, u16 offset) return ioread16(rspi->addr + offset); } +static void rspi_write_data(const struct rspi_data *rspi, u16 data) +{ + if (rspi->data_width == 8) + rspi_write8(rspi, data, RSPI_SPDR); + else /* 16 bit only */ + rspi_write16(rspi, data, RSPI_SPDR); +} + +static u16 rspi_read_data(const struct rspi_data *rspi) +{ + if (rspi->data_width == 8) + return rspi_read8(rspi, RSPI_SPDR); + else /* 16 bit only */ + return rspi_read16(rspi, RSPI_SPDR); +} + /* optional functions */ struct spi_ops { + int (*parse_platform_data)(struct rspi_data *rspi, + const struct rspi_plat_data *rspi_pd); int (*set_config_register)(const struct rspi_data *rspi, int access_size); int (*send_pio)(struct rspi_data *rspi, struct spi_message *mesg, @@ -239,6 +259,33 @@ struct spi_ops { /* * functions for RSPI */ +static int rspi_parse_platform_data(struct rspi_data *rspi, + const struct rspi_plat_data *rspi_pd) +{ + if (rspi_pd && rspi_pd->data_width) { + rspi->data_width = rspi_pd->data_width; + switch (rspi_pd->data_width) { + case 8: + rspi->spdcr = SPDCR_SPLBYTE; + break; + case 16: + rspi->spdcr = SPDCR_SPLWORD; + break; + default: + return -EINVAL; + } + } else { + /* + * Use legacy 16-bit width data access if a data_width value + * isn't defined in the platform data. + */ + rspi->data_width = 16; + rspi->spdcr = 0; + } + + return 0; +} + static int rspi_set_config_register(const struct rspi_data *rspi, int access_size) { @@ -252,7 +299,7 @@ static int rspi_set_config_register(const struct rspi_data *rspi, rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); /* Sets number of frames to be used: 1 frame */ - rspi_write8(rspi, 0x00, RSPI_SPDCR); + rspi_write8(rspi, rspi->spdcr, RSPI_SPDCR); /* Sets RSPCK, SSL, next-access delay value */ rspi_write8(rspi, 0x00, RSPI_SPCKD); @@ -275,6 +322,16 @@ static int rspi_set_config_register(const struct rspi_data *rspi, /* * functions for QSPI */ +static int qspi_parse_platform_data(struct rspi_data *rspi, + const struct rspi_plat_data *rspi_pd) +{ + /* Fixed 8-bit for now */ + rspi->data_width = 8; + rspi->spdcr = 0; + + return 0; +} + static int qspi_set_config_register(const struct rspi_data *rspi, int access_size) { @@ -289,7 +346,7 @@ static int qspi_set_config_register(const struct rspi_data *rspi, rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); /* Sets number of frames to be used: 1 frame */ - rspi_write8(rspi, 0x00, RSPI_SPDCR); + rspi_write8(rspi, rspi->spdcr, RSPI_SPDCR); /* Sets RSPCK, SSL, next-access delay value */ rspi_write8(rspi, 0x00, RSPI_SPCKD); @@ -374,7 +431,7 @@ static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg, return -ETIMEDOUT; } - rspi_write16(rspi, *data, RSPI_SPDR); + rspi_write_data(rspi, *data); data++; remain--; } @@ -401,14 +458,14 @@ static int qspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg, "%s: tx empty timeout\n", __func__); return -ETIMEDOUT; } - rspi_write8(rspi, *data++, RSPI_SPDR); + rspi_write_data(rspi, *data++); if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) { dev_err(&rspi->master->dev, "%s: receive timeout\n", __func__); return -ETIMEDOUT; } - rspi_read8(rspi, RSPI_SPDR); + rspi_read_data(rspi); remain--; } @@ -548,7 +605,7 @@ static void rspi_receive_init(const struct rspi_data *rspi) spsr = rspi_read8(rspi, RSPI_SPSR); if (spsr & SPSR_SPRF) - rspi_read16(rspi, RSPI_SPDR); /* dummy read */ + rspi_read_data(rspi); /* dummy read */ if (spsr & SPSR_OVRF) rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF, RSPI_SPSR); @@ -573,15 +630,14 @@ static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg, return -ETIMEDOUT; } /* dummy write for generate clock */ - rspi_write16(rspi, DUMMY_DATA, RSPI_SPDR); + rspi_write_data(rspi, DUMMY_DATA); if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) { dev_err(&rspi->master->dev, "%s: receive timeout\n", __func__); return -ETIMEDOUT; } - /* SPDR allows 16 or 32-bit access only */ - *data = (u8)rspi_read16(rspi, RSPI_SPDR); + *data = rspi_read_data(rspi); data++; remain--; @@ -596,7 +652,7 @@ static void qspi_receive_init(const struct rspi_data *rspi) spsr = rspi_read8(rspi, RSPI_SPSR); if (spsr & SPSR_SPRF) - rspi_read8(rspi, RSPI_SPDR); /* dummy read */ + rspi_read_data(rspi); /* dummy read */ rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR); rspi_write8(rspi, 0x00, QSPI_SPBFCR); } @@ -618,15 +674,14 @@ static int qspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg, return -ETIMEDOUT; } /* dummy write for generate clock */ - rspi_write8(rspi, DUMMY_DATA, RSPI_SPDR); + rspi_write_data(rspi, DUMMY_DATA); if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) { dev_err(&rspi->master->dev, "%s: receive timeout\n", __func__); return -ETIMEDOUT; } - /* SPDR allows 8, 16 or 32-bit access */ - *data++ = rspi_read8(rspi, RSPI_SPDR); + *data++ = rspi_read_data(rspi); remain--; } @@ -989,6 +1044,12 @@ static int rspi_probe(struct platform_device *pdev) master->transfer = rspi_transfer; master->cleanup = rspi_cleanup; + ret = ops->parse_platform_data(rspi, rspi_pd); + if (ret < 0) { + dev_err(&pdev->dev, "rspi invalid platform data.\n"); + goto error1; + } + for (i = 0; i < MAX_NUM_IRQ; i++) { irq = platform_get_irq(pdev, i); if (irq < 0) { @@ -1033,12 +1094,14 @@ error1: } static struct spi_ops rspi_ops = { + .parse_platform_data = rspi_parse_platform_data, .set_config_register = rspi_set_config_register, .send_pio = rspi_send_pio, .receive_pio = rspi_receive_pio, }; static struct spi_ops qspi_ops = { + .parse_platform_data = qspi_parse_platform_data, .set_config_register = qspi_set_config_register, .send_pio = qspi_send_pio, .receive_pio = qspi_receive_pio, diff --git a/include/linux/spi/rspi.h b/include/linux/spi/rspi.h index a25bd6f65e7f..7316dd9c7ba9 100644 --- a/include/linux/spi/rspi.h +++ b/include/linux/spi/rspi.h @@ -1,7 +1,7 @@ /* * Renesas SPI driver * - * Copyright (C) 2012 Renesas Solutions Corp. + * Copyright (C) 2012, 2013 Renesas Solutions Corp. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -22,6 +22,8 @@ #define __LINUX_SPI_RENESAS_SPI_H__ struct rspi_plat_data { + u8 data_width; /* Data register access width */ + unsigned int dma_tx_id; unsigned int dma_rx_id; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
