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author | Geert Uytterhoeven <geert+renesas@linux-m68k.org> | 2014-01-24 08:43:59 (GMT) |
---|---|---|
committer | Mark Brown <broonie@linaro.org> | 2014-01-27 20:07:07 (GMT) |
commit | 862d357f84f009fdcba22be8d6a2f82ff80ab740 (patch) | |
tree | d9b52cb46935f48629a3fcff1a0c3cac1a9d8315 /drivers | |
parent | 9372220678cd4c62992f7637b2ee36b47fa58d37 (diff) | |
download | linux-862d357f84f009fdcba22be8d6a2f82ff80ab740.tar.xz |
spi: rspi: Add support for RSPI on RZ/A1H
Add support for the RSPI variant in the RZ/A1H (r7s72100) SoC.
Main differences with RSPI on SH are:
- Lack of TX only mode, hence we always have to use full duplex
transfers,
- The Data Register must be accessed used 8-bit operations.
RSPI on RZ is matched using the new "rspi-rz" platform device name.
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/spi/spi-rspi.c | 101 |
1 files changed, 92 insertions, 9 deletions
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index d2ade5e..0c75569 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -47,7 +47,7 @@ #define RSPI_SPCKD 0x0c /* Clock Delay Register */ #define RSPI_SSLND 0x0d /* Slave Select Negation Delay Register */ #define RSPI_SPND 0x0e /* Next-Access Delay Register */ -#define RSPI_SPCR2 0x0f /* Control Register 2 */ +#define RSPI_SPCR2 0x0f /* Control Register 2 (SH only) */ #define RSPI_SPCMD0 0x10 /* Command Register 0 */ #define RSPI_SPCMD1 0x12 /* Command Register 1 */ #define RSPI_SPCMD2 0x14 /* Command Register 2 */ @@ -56,10 +56,12 @@ #define RSPI_SPCMD5 0x1a /* Command Register 5 */ #define RSPI_SPCMD6 0x1c /* Command Register 6 */ #define RSPI_SPCMD7 0x1e /* Command Register 7 */ + +/* RSPI on RZ only */ #define RSPI_SPBFCR 0x20 /* Buffer Control Register */ #define RSPI_SPBFDR 0x22 /* Buffer Data Count Setting Register */ -/*qspi only */ +/* QSPI only */ #define QSPI_SPBFCR 0x18 /* Buffer Control Register */ #define QSPI_SPBDCR 0x1a /* Buffer Data Count Register */ #define QSPI_SPBMUL0 0x1c /* Transfer Data Length Multiplier Setting Register 0 */ @@ -102,7 +104,7 @@ #define SPSR_PERF 0x08 /* Parity Error Flag */ #define SPSR_MODF 0x04 /* Mode Fault Error Flag */ #define SPSR_IDLNF 0x02 /* RSPI Idle Flag */ -#define SPSR_OVRF 0x01 /* Overrun Error Flag */ +#define SPSR_OVRF 0x01 /* Overrun Error Flag (RSPI only) */ /* SPSCR - Sequence Control Register */ #define SPSCR_SPSLN_MASK 0x07 /* Sequence Length Specification */ @@ -119,13 +121,13 @@ #define SPDCR_SPLWORD SPDCR_SPLW1 #define SPDCR_SPLBYTE SPDCR_SPLW0 #define SPDCR_SPLW 0x20 /* Access Width Specification (SH) */ -#define SPDCR_SPRDTD 0x10 /* Receive Transmit Data Select */ +#define SPDCR_SPRDTD 0x10 /* Receive Transmit Data Select (SH) */ #define SPDCR_SLSEL1 0x08 #define SPDCR_SLSEL0 0x04 -#define SPDCR_SLSEL_MASK 0x0c /* SSL1 Output Select */ +#define SPDCR_SLSEL_MASK 0x0c /* SSL1 Output Select (SH) */ #define SPDCR_SPFC1 0x02 #define SPDCR_SPFC0 0x01 -#define SPDCR_SPFC_MASK 0x03 /* Frame Count Setting (1-4) */ +#define SPDCR_SPFC_MASK 0x03 /* Frame Count Setting (1-4) (SH) */ /* SPCKD - Clock Delay Register */ #define SPCKD_SCKDL_MASK 0x07 /* Clock Delay Setting (1-8) */ @@ -168,8 +170,8 @@ #define SPCMD_CPHA 0x0001 /* Clock Phase Setting */ /* SPBFCR - Buffer Control Register */ -#define SPBFCR_TXRST 0x80 /* Transmit Buffer Data Reset (qspi only) */ -#define SPBFCR_RXRST 0x40 /* Receive Buffer Data Reset (qspi only) */ +#define SPBFCR_TXRST 0x80 /* Transmit Buffer Data Reset */ +#define SPBFCR_RXRST 0x40 /* Receive Buffer Data Reset */ #define SPBFCR_TXTRG_MASK 0x30 /* Transmit Buffer Data Triggering Number */ #define SPBFCR_RXTRG_MASK 0x07 /* Receive Buffer Data Triggering Number */ @@ -244,7 +246,7 @@ struct spi_ops { }; /* - * functions for RSPI + * functions for RSPI on legacy SH */ static int rspi_set_config_register(struct rspi_data *rspi, int access_size) { @@ -280,6 +282,39 @@ static int rspi_set_config_register(struct rspi_data *rspi, int access_size) } /* + * functions for RSPI on RZ + */ +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 transfer bit rate */ + spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1; + rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); + + /* Disable dummy transmission, set byte access */ + rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR); + rspi->byte_access = 1; + + /* Sets RSPCK, SSL, next-access delay value */ + rspi_write8(rspi, 0x00, RSPI_SPCKD); + rspi_write8(rspi, 0x00, RSPI_SSLND); + rspi_write8(rspi, 0x00, RSPI_SPND); + + /* Sets SPCMD */ + rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size); + rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); + + /* Sets RSPI mode */ + rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR); + + return 0; +} + +/* * functions for QSPI */ static int qspi_set_config_register(struct rspi_data *rspi, int access_size) @@ -520,6 +555,13 @@ static void rspi_receive_init(const struct rspi_data *rspi) RSPI_SPSR); } +static void rspi_rz_receive_init(const struct rspi_data *rspi) +{ + rspi_receive_init(rspi); + rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR); + rspi_write8(rspi, 0, RSPI_SPBFCR); +} + static void qspi_receive_init(const struct rspi_data *rspi) { u8 spsr; @@ -706,6 +748,41 @@ static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi, return 0; } +static int rspi_rz_transfer_out_in(struct rspi_data *rspi, + struct spi_transfer *xfer) +{ + int remain = xfer->len, ret; + const u8 *tx_buf = xfer->tx_buf; + u8 *rx_buf = xfer->rx_buf; + u8 data; + + rspi_rz_receive_init(rspi); + + while (remain > 0) { + data = tx_buf ? *tx_buf++ : DUMMY_DATA; + ret = rspi_data_out_in(rspi, data); + if (ret < 0) + return ret; + if (rx_buf) + *rx_buf++ = ret; + remain--; + } + + /* Wait for the last transmission */ + rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE); + + return 0; +} + +static int rspi_rz_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct rspi_data *rspi = spi_master_get_devdata(master); + + return rspi_rz_transfer_out_in(rspi, xfer); +} + static int qspi_transfer_out_in(struct rspi_data *rspi, struct spi_transfer *xfer) { @@ -1041,6 +1118,11 @@ static struct spi_ops rspi_ops = { .transfer_one = rspi_transfer_one, }; +static struct spi_ops rspi_rz_ops = { + .set_config_register = rspi_rz_set_config_register, + .transfer_one = rspi_rz_transfer_one, +}; + static struct spi_ops qspi_ops = { .set_config_register = qspi_set_config_register, .transfer_one = qspi_transfer_one, @@ -1048,6 +1130,7 @@ static struct spi_ops qspi_ops = { static struct platform_device_id spi_driver_ids[] = { { "rspi", (kernel_ulong_t)&rspi_ops }, + { "rspi-rz", (kernel_ulong_t)&rspi_rz_ops }, { "qspi", (kernel_ulong_t)&qspi_ops }, {}, }; |