| From 54b29f6f07854342f81d85463b16a316106c35f6 Mon Sep 17 00:00:00 2001 |
| From: Geert Uytterhoeven <geert+renesas@linux-m68k.org> |
| Date: Fri, 24 Jan 2014 09:44:00 +0100 |
| Subject: spi: rspi: Add support for loopback mode |
| |
| Add support for specifying loopback mode. |
| |
| Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> |
| Signed-off-by: Mark Brown <broonie@linaro.org> |
| (cherry picked from commit 06a7a3cff042a36fb7e6af71039a17c6d1a6d90f) |
| Signed-off-by: Simon Horman <horms+renesas@verge.net.au> |
| --- |
| drivers/spi/spi-rspi.c | 22 ++++++++++++++-------- |
| 1 file changed, 14 insertions(+), 8 deletions(-) |
| |
| diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c |
| index 0c7556978d2e..28db8770aaf3 100644 |
| --- a/drivers/spi/spi-rspi.c |
| +++ b/drivers/spi/spi-rspi.c |
| @@ -183,8 +183,9 @@ struct rspi_data { |
| struct spi_master *master; |
| wait_queue_head_t wait; |
| struct clk *clk; |
| - u8 spsr; |
| u16 spcmd; |
| + u8 spsr; |
| + u8 sppcr; |
| int rx_irq, tx_irq; |
| const struct spi_ops *ops; |
| |
| @@ -252,8 +253,8 @@ static int rspi_set_config_register(struct rspi_data *rspi, int access_size) |
| { |
| int spbr; |
| |
| - /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */ |
| - rspi_write8(rspi, 0x00, RSPI_SPPCR); |
| + /* Sets output mode, MOSI signal, and (optionally) loopback */ |
| + rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); |
| |
| /* Sets transfer bit rate */ |
| spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1; |
| @@ -288,8 +289,8 @@ static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size) |
| { |
| int spbr; |
| |
| - /* Sets output mode */ |
| - rspi_write8(rspi, 0x00, RSPI_SPPCR); |
| + /* Sets output mode, MOSI signal, and (optionally) loopback */ |
| + rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); |
| |
| /* Sets transfer bit rate */ |
| spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1; |
| @@ -322,8 +323,8 @@ static int qspi_set_config_register(struct rspi_data *rspi, int access_size) |
| u16 spcmd; |
| int spbr; |
| |
| - /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */ |
| - rspi_write8(rspi, 0x00, RSPI_SPPCR); |
| + /* Sets output mode, MOSI signal, and (optionally) loopback */ |
| + rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); |
| |
| /* Sets transfer bit rate */ |
| spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz); |
| @@ -829,6 +830,11 @@ static int rspi_setup(struct spi_device *spi) |
| if (spi->mode & SPI_CPHA) |
| rspi->spcmd |= SPCMD_CPHA; |
| |
| + /* CMOS output mode and MOSI signal from previous transfer */ |
| + rspi->sppcr = 0; |
| + if (spi->mode & SPI_LOOP) |
| + rspi->sppcr |= SPPCR_SPLP; |
| + |
| set_config_register(rspi, 8); |
| |
| return 0; |
| @@ -1050,7 +1056,7 @@ static int rspi_probe(struct platform_device *pdev) |
| master->cleanup = rspi_cleanup; |
| master->prepare_message = rspi_prepare_message; |
| master->unprepare_message = rspi_unprepare_message; |
| - master->mode_bits = SPI_CPHA | SPI_CPOL; |
| + master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP; |
| |
| ret = platform_get_irq_byname(pdev, "rx"); |
| if (ret < 0) { |
| -- |
| 2.1.2 |
| |