From 86fc593599c11b62a11c85b4d7b709089df15c29 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Richard=20R=C3=B6jfors?= Date: Fri, 13 Nov 2009 12:28:49 +0100 Subject: [PATCH] xilinx_spi: Switch to iomem functions and support little endian. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This patch changes the out_(be)(8|16|32) and in_(be)(8|16|32) calls to 32 bits ioread/iowrite. The read and write function are attached to the internal struct as callbacks, callback is selected depending on endianess. This will also build on platforms not supporting the in/out calls for instance x86. Acked-by: Grant Likely Tested-by: John Linn Signed-off-by: Richard Röjfors Signed-off-by: Grant Likely --- drivers/spi/Kconfig | 2 +- drivers/spi/xilinx_spi.c | 96 +++++++++++++++++++--------------- include/linux/spi/xilinx_spi.h | 2 + 3 files changed, 57 insertions(+), 43 deletions(-) diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index f34a2d16d18f..b528271c72ef 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -244,7 +244,7 @@ config SPI_TXX9 config SPI_XILINX tristate "Xilinx SPI controller" - depends on EXPERIMENTAL + depends on HAS_IOMEM && EXPERIMENTAL select SPI_BITBANG select SPI_XILINX_OF if (XILINX_VIRTEX || MICROBLAZE) help diff --git a/drivers/spi/xilinx_spi.c b/drivers/spi/xilinx_spi.c index 69fa26d82ce4..135a3a5931a4 100644 --- a/drivers/spi/xilinx_spi.c +++ b/drivers/spi/xilinx_spi.c @@ -27,7 +27,7 @@ /* Register definitions as per "OPB Serial Peripheral Interface (SPI) (v1.00e) * Product Specification", DS464 */ -#define XSPI_CR_OFFSET 0x62 /* 16-bit Control Register */ +#define XSPI_CR_OFFSET 0x60 /* 16-bit Control Register */ #define XSPI_CR_ENABLE 0x02 #define XSPI_CR_MASTER_MODE 0x04 @@ -39,7 +39,7 @@ #define XSPI_CR_MANUAL_SSELECT 0x80 #define XSPI_CR_TRANS_INHIBIT 0x100 -#define XSPI_SR_OFFSET 0x67 /* 8-bit Status Register */ +#define XSPI_SR_OFFSET 0x64 /* 8-bit Status Register */ #define XSPI_SR_RX_EMPTY_MASK 0x01 /* Receive FIFO is empty */ #define XSPI_SR_RX_FULL_MASK 0x02 /* Receive FIFO is full */ @@ -47,8 +47,8 @@ #define XSPI_SR_TX_FULL_MASK 0x08 /* Transmit FIFO is full */ #define XSPI_SR_MODE_FAULT_MASK 0x10 /* Mode fault error */ -#define XSPI_TXD_OFFSET 0x6b /* 8-bit Data Transmit Register */ -#define XSPI_RXD_OFFSET 0x6f /* 8-bit Data Receive Register */ +#define XSPI_TXD_OFFSET 0x68 /* 8-bit Data Transmit Register */ +#define XSPI_RXD_OFFSET 0x6c /* 8-bit Data Receive Register */ #define XSPI_SSR_OFFSET 0x70 /* 32-bit Slave Select Register */ @@ -86,25 +86,29 @@ struct xilinx_spi { u8 *rx_ptr; /* pointer in the Tx buffer */ const u8 *tx_ptr; /* pointer in the Rx buffer */ int remaining_bytes; /* the number of bytes left to transfer */ + unsigned int (*read_fn) (void __iomem *); + void (*write_fn) (u32, void __iomem *); }; -static void xspi_init_hw(void __iomem *regs_base) +static void xspi_init_hw(struct xilinx_spi *xspi) { + void __iomem *regs_base = xspi->regs; + /* Reset the SPI device */ - out_be32(regs_base + XIPIF_V123B_RESETR_OFFSET, - XIPIF_V123B_RESET_MASK); + xspi->write_fn(XIPIF_V123B_RESET_MASK, + regs_base + XIPIF_V123B_RESETR_OFFSET); /* Disable all the interrupts just in case */ - out_be32(regs_base + XIPIF_V123B_IIER_OFFSET, 0); + xspi->write_fn(0, regs_base + XIPIF_V123B_IIER_OFFSET); /* Enable the global IPIF interrupt */ - out_be32(regs_base + XIPIF_V123B_DGIER_OFFSET, - XIPIF_V123B_GINTR_ENABLE); + xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, + regs_base + XIPIF_V123B_DGIER_OFFSET); /* Deselect the slave on the SPI bus */ - out_be32(regs_base + XSPI_SSR_OFFSET, 0xffff); + xspi->write_fn(0xffff, regs_base + XSPI_SSR_OFFSET); /* Disable the transmitter, enable Manual Slave Select Assertion, * put SPI controller into master mode, and enable it */ - out_be16(regs_base + XSPI_CR_OFFSET, - XSPI_CR_TRANS_INHIBIT | XSPI_CR_MANUAL_SSELECT - | XSPI_CR_MASTER_MODE | XSPI_CR_ENABLE); + xspi->write_fn(XSPI_CR_TRANS_INHIBIT | XSPI_CR_MANUAL_SSELECT | + XSPI_CR_MASTER_MODE | XSPI_CR_ENABLE, + regs_base + XSPI_CR_OFFSET); } static void xilinx_spi_chipselect(struct spi_device *spi, int is_on) @@ -113,16 +117,16 @@ static void xilinx_spi_chipselect(struct spi_device *spi, int is_on) if (is_on == BITBANG_CS_INACTIVE) { /* Deselect the slave on the SPI bus */ - out_be32(xspi->regs + XSPI_SSR_OFFSET, 0xffff); + xspi->write_fn(0xffff, xspi->regs + XSPI_SSR_OFFSET); } else if (is_on == BITBANG_CS_ACTIVE) { /* Set the SPI clock phase and polarity */ - u16 cr = in_be16(xspi->regs + XSPI_CR_OFFSET) + u16 cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET) & ~XSPI_CR_MODE_MASK; if (spi->mode & SPI_CPHA) cr |= XSPI_CR_CPHA; if (spi->mode & SPI_CPOL) cr |= XSPI_CR_CPOL; - out_be16(xspi->regs + XSPI_CR_OFFSET, cr); + xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); /* We do not check spi->max_speed_hz here as the SPI clock * frequency is not software programmable (the IP block design @@ -130,8 +134,8 @@ static void xilinx_spi_chipselect(struct spi_device *spi, int is_on) */ /* Activate the chip select */ - out_be32(xspi->regs + XSPI_SSR_OFFSET, - ~(0x0001 << spi->chip_select)); + xspi->write_fn(~(0x0001 << spi->chip_select), + xspi->regs + XSPI_SSR_OFFSET); } } @@ -178,15 +182,15 @@ static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi) u8 sr; /* Fill the Tx FIFO with as many bytes as possible */ - sr = in_8(xspi->regs + XSPI_SR_OFFSET); + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); while ((sr & XSPI_SR_TX_FULL_MASK) == 0 && xspi->remaining_bytes > 0) { - if (xspi->tx_ptr) { - out_8(xspi->regs + XSPI_TXD_OFFSET, *xspi->tx_ptr++); - } else { - out_8(xspi->regs + XSPI_TXD_OFFSET, 0); - } + if (xspi->tx_ptr) + xspi->write_fn(*xspi->tx_ptr++, + xspi->regs + XSPI_TXD_OFFSET); + else + xspi->write_fn(0, xspi->regs + XSPI_TXD_OFFSET); xspi->remaining_bytes--; - sr = in_8(xspi->regs + XSPI_SR_OFFSET); + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); } } @@ -208,18 +212,19 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) /* Enable the transmit empty interrupt, which we use to determine * progress on the transmission. */ - ipif_ier = in_be32(xspi->regs + XIPIF_V123B_IIER_OFFSET); - out_be32(xspi->regs + XIPIF_V123B_IIER_OFFSET, - ipif_ier | XSPI_INTR_TX_EMPTY); + ipif_ier = xspi->read_fn(xspi->regs + XIPIF_V123B_IIER_OFFSET); + xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY, + xspi->regs + XIPIF_V123B_IIER_OFFSET); /* Start the transfer by not inhibiting the transmitter any longer */ - cr = in_be16(xspi->regs + XSPI_CR_OFFSET) & ~XSPI_CR_TRANS_INHIBIT; - out_be16(xspi->regs + XSPI_CR_OFFSET, cr); + cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET) & + ~XSPI_CR_TRANS_INHIBIT; + xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); wait_for_completion(&xspi->done); /* Disable the transmit empty interrupt */ - out_be32(xspi->regs + XIPIF_V123B_IIER_OFFSET, ipif_ier); + xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET); return t->len - xspi->remaining_bytes; } @@ -236,8 +241,8 @@ static irqreturn_t xilinx_spi_irq(int irq, void *dev_id) u32 ipif_isr; /* Get the IPIF interrupts, and clear them immediately */ - ipif_isr = in_be32(xspi->regs + XIPIF_V123B_IISR_OFFSET); - out_be32(xspi->regs + XIPIF_V123B_IISR_OFFSET, ipif_isr); + ipif_isr = xspi->read_fn(xspi->regs + XIPIF_V123B_IISR_OFFSET); + xspi->write_fn(ipif_isr, xspi->regs + XIPIF_V123B_IISR_OFFSET); if (ipif_isr & XSPI_INTR_TX_EMPTY) { /* Transmission completed */ u16 cr; @@ -248,20 +253,20 @@ static irqreturn_t xilinx_spi_irq(int irq, void *dev_id) * transmitter while the Isr refills the transmit register/FIFO, * or make sure it is stopped if we're done. */ - cr = in_be16(xspi->regs + XSPI_CR_OFFSET); - out_be16(xspi->regs + XSPI_CR_OFFSET, - cr | XSPI_CR_TRANS_INHIBIT); + cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET); + xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT, + xspi->regs + XSPI_CR_OFFSET); /* Read out all the data from the Rx FIFO */ - sr = in_8(xspi->regs + XSPI_SR_OFFSET); + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) { u8 data; - data = in_8(xspi->regs + XSPI_RXD_OFFSET); + data = xspi->read_fn(xspi->regs + XSPI_RXD_OFFSET); if (xspi->rx_ptr) { *xspi->rx_ptr++ = data; } - sr = in_8(xspi->regs + XSPI_SR_OFFSET); + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); } /* See if there is more data to send */ @@ -270,7 +275,7 @@ static irqreturn_t xilinx_spi_irq(int irq, void *dev_id) /* Start the transfer by not inhibiting the * transmitter any longer */ - out_be16(xspi->regs + XSPI_CR_OFFSET, cr); + xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); } else { /* No more data to send. * Indicate the transfer is completed. @@ -325,9 +330,16 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem, xspi->mem = *mem; xspi->irq = irq; + if (pdata->little_endian) { + xspi->read_fn = ioread32; + xspi->write_fn = iowrite32; + } else { + xspi->read_fn = ioread32be; + xspi->write_fn = iowrite32be; + } /* SPI controller initializations */ - xspi_init_hw(xspi->regs); + xspi_init_hw(xspi); /* Register for SPI Interrupt */ ret = request_irq(xspi->irq, xilinx_spi_irq, 0, XILINX_SPI_NAME, xspi); diff --git a/include/linux/spi/xilinx_spi.h b/include/linux/spi/xilinx_spi.h index 06df0aba3aee..a705ad85eebe 100644 --- a/include/linux/spi/xilinx_spi.h +++ b/include/linux/spi/xilinx_spi.h @@ -4,11 +4,13 @@ /** * struct xspi_platform_data - Platform data of the Xilinx SPI driver * @num_chipselect: Number of chip select by the IP + * @little_endian If registers should be accessed little endian or not * @devices: Devices to add when the driver is probed. * @num_devices: Number of devices in the devices array. */ struct xspi_platform_data { u16 num_chipselect; + bool little_endian; struct spi_board_info *devices; u8 num_devices; }; -- 2.20.1