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author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2008-08-07 09:55:03 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2008-08-07 09:55:03 +0100 |
commit | 4fb8af10d0fd09372d52966b76922b9e82bbc950 (patch) | |
tree | d240e4d40357583e3f3eb228dccf20122a5b31ed /drivers/spi | |
parent | f44f82e8a20b98558486eb14497b2f71c78fa325 (diff) | |
parent | 64a99d2a8c3ed5c4e39f3ae1cc682aa8fd3977fc (diff) | |
download | lwn-4fb8af10d0fd09372d52966b76922b9e82bbc950.tar.gz lwn-4fb8af10d0fd09372d52966b76922b9e82bbc950.zip |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/Kconfig | 6 | ||||
-rw-r--r-- | drivers/spi/Makefile | 1 | ||||
-rw-r--r-- | drivers/spi/atmel_spi.c | 17 | ||||
-rw-r--r-- | drivers/spi/mpc52xx_psc_spi.c | 22 | ||||
-rw-r--r-- | drivers/spi/orion_spi.c | 574 | ||||
-rw-r--r-- | drivers/spi/spi.c | 139 | ||||
-rw-r--r-- | drivers/spi/spi_s3c24xx.c | 26 |
7 files changed, 711 insertions, 74 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 2303521b4f09..b9d0efb6803f 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -149,6 +149,12 @@ config SPI_OMAP24XX SPI master controller for OMAP24xx/OMAP34xx Multichannel SPI (McSPI) modules. +config SPI_ORION + tristate "Orion SPI master (EXPERIMENTAL)" + depends on PLAT_ORION && EXPERIMENTAL + help + This enables using the SPI master controller on the Orion chips. + config SPI_PXA2XX tristate "PXA2xx SSP SPI master" depends on ARCH_PXA && EXPERIMENTAL diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 7fca043ce723..ccf18de34e1e 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_SPI_LM70_LLP) += spi_lm70llp.o obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o obj-$(CONFIG_SPI_OMAP_UWIRE) += omap_uwire.o obj-$(CONFIG_SPI_OMAP24XX) += omap2_mcspi.o +obj-$(CONFIG_SPI_ORION) += orion_spi.o obj-$(CONFIG_SPI_MPC52xx_PSC) += mpc52xx_psc_spi.o obj-$(CONFIG_SPI_MPC83xx) += spi_mpc83xx.o obj-$(CONFIG_SPI_S3C24XX_GPIO) += spi_s3c24xx_gpio.o diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c index 0c7165660853..95190c619c10 100644 --- a/drivers/spi/atmel_spi.c +++ b/drivers/spi/atmel_spi.c @@ -184,7 +184,8 @@ static void atmel_spi_next_xfer(struct spi_master *master, { struct atmel_spi *as = spi_master_get_devdata(master); struct spi_transfer *xfer; - u32 len, remaining, total; + u32 len, remaining; + u32 ieval; dma_addr_t tx_dma, rx_dma; if (!as->current_transfer) @@ -197,6 +198,8 @@ static void atmel_spi_next_xfer(struct spi_master *master, xfer = NULL; if (xfer) { + spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); + len = xfer->len; atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); remaining = xfer->len - len; @@ -234,6 +237,8 @@ static void atmel_spi_next_xfer(struct spi_master *master, as->next_transfer = xfer; if (xfer) { + u32 total; + total = len; atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); as->next_remaining_bytes = total - len; @@ -250,9 +255,11 @@ static void atmel_spi_next_xfer(struct spi_master *master, " next xfer %p: len %u tx %p/%08x rx %p/%08x\n", xfer, xfer->len, xfer->tx_buf, xfer->tx_dma, xfer->rx_buf, xfer->rx_dma); + ieval = SPI_BIT(ENDRX) | SPI_BIT(OVRES); } else { spi_writel(as, RNCR, 0); spi_writel(as, TNCR, 0); + ieval = SPI_BIT(RXBUFF) | SPI_BIT(ENDRX) | SPI_BIT(OVRES); } /* REVISIT: We're waiting for ENDRX before we start the next @@ -265,7 +272,7 @@ static void atmel_spi_next_xfer(struct spi_master *master, * * It should be doable, though. Just not now... */ - spi_writel(as, IER, SPI_BIT(ENDRX) | SPI_BIT(OVRES)); + spi_writel(as, IER, ieval); spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN)); } @@ -396,7 +403,7 @@ atmel_spi_interrupt(int irq, void *dev_id) ret = IRQ_HANDLED; - spi_writel(as, IDR, (SPI_BIT(ENDTX) | SPI_BIT(ENDRX) + spi_writel(as, IDR, (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX) | SPI_BIT(OVRES))); /* @@ -418,7 +425,7 @@ atmel_spi_interrupt(int irq, void *dev_id) if (xfer->delay_usecs) udelay(xfer->delay_usecs); - dev_warn(master->dev.parent, "fifo overrun (%u/%u remaining)\n", + dev_warn(master->dev.parent, "overrun (%u/%u remaining)\n", spi_readl(as, TCR), spi_readl(as, RCR)); /* @@ -442,7 +449,7 @@ atmel_spi_interrupt(int irq, void *dev_id) spi_readl(as, SR); atmel_spi_msg_done(master, as, msg, -EIO, 0); - } else if (pending & SPI_BIT(ENDRX)) { + } else if (pending & (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX))) { ret = IRQ_HANDLED; spi_writel(as, IDR, pending); diff --git a/drivers/spi/mpc52xx_psc_spi.c b/drivers/spi/mpc52xx_psc_spi.c index 604e5f0a2d95..25eda71f4bf4 100644 --- a/drivers/spi/mpc52xx_psc_spi.c +++ b/drivers/spi/mpc52xx_psc_spi.c @@ -148,7 +148,6 @@ static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi, unsigned rfalarm; unsigned send_at_once = MPC52xx_PSC_BUFSIZE; unsigned recv_at_once; - unsigned bpw = mps->bits_per_word / 8; if (!t->tx_buf && !t->rx_buf && t->len) return -EINVAL; @@ -164,22 +163,15 @@ static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi, } dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once); - if (tx_buf) { - for (; send_at_once; sb++, send_at_once--) { - /* set EOF flag */ - if (mps->bits_per_word - && (sb + 1) % bpw == 0) - out_8(&psc->ircr2, 0x01); + for (; send_at_once; sb++, send_at_once--) { + /* set EOF flag before the last word is sent */ + if (send_at_once == 1) + out_8(&psc->ircr2, 0x01); + + if (tx_buf) out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]); - } - } else { - for (; send_at_once; sb++, send_at_once--) { - /* set EOF flag */ - if (mps->bits_per_word - && ((sb + 1) % bpw) == 0) - out_8(&psc->ircr2, 0x01); + else out_8(&psc->mpc52xx_psc_buffer_8, 0); - } } diff --git a/drivers/spi/orion_spi.c b/drivers/spi/orion_spi.c new file mode 100644 index 000000000000..c4eaacd6e553 --- /dev/null +++ b/drivers/spi/orion_spi.c @@ -0,0 +1,574 @@ +/* + * orion_spi.c -- Marvell Orion SPI controller driver + * + * Author: Shadi Ammouri <shadi@marvell.com> + * Copyright (C) 2007-2008 Marvell Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/spi/spi.h> +#include <linux/spi/orion_spi.h> +#include <asm/unaligned.h> + +#define DRIVER_NAME "orion_spi" + +#define ORION_NUM_CHIPSELECTS 1 /* only one slave is supported*/ +#define ORION_SPI_WAIT_RDY_MAX_LOOP 2000 /* in usec */ + +#define ORION_SPI_IF_CTRL_REG 0x00 +#define ORION_SPI_IF_CONFIG_REG 0x04 +#define ORION_SPI_DATA_OUT_REG 0x08 +#define ORION_SPI_DATA_IN_REG 0x0c +#define ORION_SPI_INT_CAUSE_REG 0x10 + +#define ORION_SPI_IF_8_16_BIT_MODE (1 << 5) +#define ORION_SPI_CLK_PRESCALE_MASK 0x1F + +struct orion_spi { + struct work_struct work; + + /* Lock access to transfer list. */ + spinlock_t lock; + + struct list_head msg_queue; + struct spi_master *master; + void __iomem *base; + unsigned int max_speed; + unsigned int min_speed; + struct orion_spi_info *spi_info; +}; + +static struct workqueue_struct *orion_spi_wq; + +static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg) +{ + return orion_spi->base + reg; +} + +static inline void +orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask) +{ + void __iomem *reg_addr = spi_reg(orion_spi, reg); + u32 val; + + val = readl(reg_addr); + val |= mask; + writel(val, reg_addr); +} + +static inline void +orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask) +{ + void __iomem *reg_addr = spi_reg(orion_spi, reg); + u32 val; + + val = readl(reg_addr); + val &= ~mask; + writel(val, reg_addr); +} + +static int orion_spi_set_transfer_size(struct orion_spi *orion_spi, int size) +{ + if (size == 16) { + orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG, + ORION_SPI_IF_8_16_BIT_MODE); + } else if (size == 8) { + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG, + ORION_SPI_IF_8_16_BIT_MODE); + } else { + pr_debug("Bad bits per word value %d (only 8 or 16 are " + "allowed).\n", size); + return -EINVAL; + } + + return 0; +} + +static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed) +{ + u32 tclk_hz; + u32 rate; + u32 prescale; + u32 reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + + tclk_hz = orion_spi->spi_info->tclk; + + /* + * the supported rates are: 4,6,8...30 + * round up as we look for equal or less speed + */ + rate = DIV_ROUND_UP(tclk_hz, speed); + rate = roundup(rate, 2); + + /* check if requested speed is too small */ + if (rate > 30) + return -EINVAL; + + if (rate < 4) + rate = 4; + + /* Convert the rate to SPI clock divisor value. */ + prescale = 0x10 + rate/2; + + reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + reg = ((reg & ~ORION_SPI_CLK_PRESCALE_MASK) | prescale); + writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + + return 0; +} + +/* + * called only when no transfer is active on the bus + */ +static int +orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct orion_spi *orion_spi; + unsigned int speed = spi->max_speed_hz; + unsigned int bits_per_word = spi->bits_per_word; + int rc; + + orion_spi = spi_master_get_devdata(spi->master); + + if ((t != NULL) && t->speed_hz) + speed = t->speed_hz; + + if ((t != NULL) && t->bits_per_word) + bits_per_word = t->bits_per_word; + + rc = orion_spi_baudrate_set(spi, speed); + if (rc) + return rc; + + return orion_spi_set_transfer_size(orion_spi, bits_per_word); +} + +static void orion_spi_set_cs(struct orion_spi *orion_spi, int enable) +{ + if (enable) + orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); + else + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); +} + +static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi) +{ + int i; + + for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) { + if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG))) + return 1; + else + udelay(1); + } + + return -1; +} + +static inline int +orion_spi_write_read_8bit(struct spi_device *spi, + const u8 **tx_buf, u8 **rx_buf) +{ + void __iomem *tx_reg, *rx_reg, *int_reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG); + rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG); + int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG); + + /* clear the interrupt cause register */ + writel(0x0, int_reg); + + if (tx_buf && *tx_buf) + writel(*(*tx_buf)++, tx_reg); + else + writel(0, tx_reg); + + if (orion_spi_wait_till_ready(orion_spi) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + return -1; + } + + if (rx_buf && *rx_buf) + *(*rx_buf)++ = readl(rx_reg); + + return 1; +} + +static inline int +orion_spi_write_read_16bit(struct spi_device *spi, + const u16 **tx_buf, u16 **rx_buf) +{ + void __iomem *tx_reg, *rx_reg, *int_reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG); + rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG); + int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG); + + /* clear the interrupt cause register */ + writel(0x0, int_reg); + + if (tx_buf && *tx_buf) + writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg); + else + writel(0, tx_reg); + + if (orion_spi_wait_till_ready(orion_spi) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + return -1; + } + + if (rx_buf && *rx_buf) + put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++); + + return 1; +} + +static unsigned int +orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer) +{ + struct orion_spi *orion_spi; + unsigned int count; + int word_len; + + orion_spi = spi_master_get_devdata(spi->master); + word_len = spi->bits_per_word; + count = xfer->len; + + if (word_len == 8) { + const u8 *tx = xfer->tx_buf; + u8 *rx = xfer->rx_buf; + + do { + if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0) + goto out; + count--; + } while (count); + } else if (word_len == 16) { + const u16 *tx = xfer->tx_buf; + u16 *rx = xfer->rx_buf; + + do { + if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0) + goto out; + count -= 2; + } while (count); + } + +out: + return xfer->len - count; +} + + +static void orion_spi_work(struct work_struct *work) +{ + struct orion_spi *orion_spi = + container_of(work, struct orion_spi, work); + + spin_lock_irq(&orion_spi->lock); + while (!list_empty(&orion_spi->msg_queue)) { + struct spi_message *m; + struct spi_device *spi; + struct spi_transfer *t = NULL; + int par_override = 0; + int status = 0; + int cs_active = 0; + + m = container_of(orion_spi->msg_queue.next, struct spi_message, + queue); + + list_del_init(&m->queue); + spin_unlock_irq(&orion_spi->lock); + + spi = m->spi; + + /* Load defaults */ + status = orion_spi_setup_transfer(spi, NULL); + + if (status < 0) + goto msg_done; + + list_for_each_entry(t, &m->transfers, transfer_list) { + if (par_override || t->speed_hz || t->bits_per_word) { + par_override = 1; + status = orion_spi_setup_transfer(spi, t); + if (status < 0) + break; + if (!t->speed_hz && !t->bits_per_word) + par_override = 0; + } + + if (!cs_active) { + orion_spi_set_cs(orion_spi, 1); + cs_active = 1; + } + + if (t->len) + m->actual_length += + orion_spi_write_read(spi, t); + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (t->cs_change) { + orion_spi_set_cs(orion_spi, 0); + cs_active = 0; + } + } + +msg_done: + if (cs_active) + orion_spi_set_cs(orion_spi, 0); + + m->status = status; + m->complete(m->context); + + spin_lock_irq(&orion_spi->lock); + } + + spin_unlock_irq(&orion_spi->lock); +} + +static int __init orion_spi_reset(struct orion_spi *orion_spi) +{ + /* Verify that the CS is deasserted */ + orion_spi_set_cs(orion_spi, 0); + + return 0; +} + +static int orion_spi_setup(struct spi_device *spi) +{ + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + + if (spi->mode) { + dev_err(&spi->dev, "setup: unsupported mode bits %x\n", + spi->mode); + return -EINVAL; + } + + if (spi->bits_per_word == 0) + spi->bits_per_word = 8; + + if ((spi->max_speed_hz == 0) + || (spi->max_speed_hz > orion_spi->max_speed)) + spi->max_speed_hz = orion_spi->max_speed; + + if (spi->max_speed_hz < orion_spi->min_speed) { + dev_err(&spi->dev, "setup: requested speed too low %d Hz\n", + spi->max_speed_hz); + return -EINVAL; + } + + /* + * baudrate & width will be set orion_spi_setup_transfer + */ + return 0; +} + +static int orion_spi_transfer(struct spi_device *spi, struct spi_message *m) +{ + struct orion_spi *orion_spi; + struct spi_transfer *t = NULL; + unsigned long flags; + + m->actual_length = 0; + m->status = 0; + + /* reject invalid messages and transfers */ + if (list_empty(&m->transfers) || !m->complete) + return -EINVAL; + + orion_spi = spi_master_get_devdata(spi->master); + + list_for_each_entry(t, &m->transfers, transfer_list) { + unsigned int bits_per_word = spi->bits_per_word; + + if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) { + dev_err(&spi->dev, + "message rejected : " + "invalid transfer data buffers\n"); + goto msg_rejected; + } + + if ((t != NULL) && t->bits_per_word) + bits_per_word = t->bits_per_word; + + if ((bits_per_word != 8) && (bits_per_word != 16)) { + dev_err(&spi->dev, + "message rejected : " + "invalid transfer bits_per_word (%d bits)\n", + bits_per_word); + goto msg_rejected; + } + /*make sure buffer length is even when working in 16 bit mode*/ + if ((t != NULL) && (t->bits_per_word == 16) && (t->len & 1)) { + dev_err(&spi->dev, + "message rejected : " + "odd data length (%d) while in 16 bit mode\n", + t->len); + goto msg_rejected; + } + + if (t->speed_hz < orion_spi->min_speed) { + dev_err(&spi->dev, + "message rejected : " + "device min speed (%d Hz) exceeds " + "required transfer speed (%d Hz)\n", + orion_spi->min_speed, t->speed_hz); + goto msg_rejected; + } + } + + + spin_lock_irqsave(&orion_spi->lock, flags); + list_add_tail(&m->queue, &orion_spi->msg_queue); + queue_work(orion_spi_wq, &orion_spi->work); + spin_unlock_irqrestore(&orion_spi->lock, flags); + + return 0; +msg_rejected: + /* Message rejected and not queued */ + m->status = -EINVAL; + if (m->complete) + m->complete(m->context); + return -EINVAL; +} + +static int __init orion_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct orion_spi *spi; + struct resource *r; + struct orion_spi_info *spi_info; + int status = 0; + + spi_info = pdev->dev.platform_data; + + master = spi_alloc_master(&pdev->dev, sizeof *spi); + if (master == NULL) { + dev_dbg(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + + if (pdev->id != -1) + master->bus_num = pdev->id; + + master->setup = orion_spi_setup; + master->transfer = orion_spi_transfer; + master->num_chipselect = ORION_NUM_CHIPSELECTS; + + dev_set_drvdata(&pdev->dev, master); + + spi = spi_master_get_devdata(master); + spi->master = master; + spi->spi_info = spi_info; + + spi->max_speed = DIV_ROUND_UP(spi_info->tclk, 4); + spi->min_speed = DIV_ROUND_UP(spi_info->tclk, 30); + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (r == NULL) { + status = -ENODEV; + goto out; + } + + if (!request_mem_region(r->start, (r->end - r->start) + 1, + pdev->dev.bus_id)) { + status = -EBUSY; + goto out; + } + spi->base = ioremap(r->start, SZ_1K); + + INIT_WORK(&spi->work, orion_spi_work); + + spin_lock_init(&spi->lock); + INIT_LIST_HEAD(&spi->msg_queue); + + if (orion_spi_reset(spi) < 0) + goto out_rel_mem; + + status = spi_register_master(master); + if (status < 0) + goto out_rel_mem; + + return status; + +out_rel_mem: + release_mem_region(r->start, (r->end - r->start) + 1); + +out: + spi_master_put(master); + return status; +} + + +static int __exit orion_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master; + struct orion_spi *spi; + struct resource *r; + + master = dev_get_drvdata(&pdev->dev); + spi = spi_master_get_devdata(master); + + cancel_work_sync(&spi->work); + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(r->start, (r->end - r->start) + 1); + + spi_unregister_master(master); + + return 0; +} + +MODULE_ALIAS("platform:" DRIVER_NAME); + +static struct platform_driver orion_spi_driver = { + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, + .remove = __exit_p(orion_spi_remove), +}; + +static int __init orion_spi_init(void) +{ + orion_spi_wq = create_singlethread_workqueue( + orion_spi_driver.driver.name); + if (orion_spi_wq == NULL) + return -ENOMEM; + + return platform_driver_probe(&orion_spi_driver, orion_spi_probe); +} +module_init(orion_spi_init); + +static void __exit orion_spi_exit(void) +{ + flush_workqueue(orion_spi_wq); + platform_driver_unregister(&orion_spi_driver); + + destroy_workqueue(orion_spi_wq); +} +module_exit(orion_spi_exit); + +MODULE_DESCRIPTION("Orion SPI driver"); +MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ecca4a6a6f94..964124b60db2 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -178,6 +178,96 @@ struct boardinfo { static LIST_HEAD(board_list); static DEFINE_MUTEX(board_lock); +/** + * spi_alloc_device - Allocate a new SPI device + * @master: Controller to which device is connected + * Context: can sleep + * + * Allows a driver to allocate and initialize a spi_device without + * registering it immediately. This allows a driver to directly + * fill the spi_device with device parameters before calling + * spi_add_device() on it. + * + * Caller is responsible to call spi_add_device() on the returned + * spi_device structure to add it to the SPI master. If the caller + * needs to discard the spi_device without adding it, then it should + * call spi_dev_put() on it. + * + * Returns a pointer to the new device, or NULL. + */ +struct spi_device *spi_alloc_device(struct spi_master *master) +{ + struct spi_device *spi; + struct device *dev = master->dev.parent; + + if (!spi_master_get(master)) + return NULL; + + spi = kzalloc(sizeof *spi, GFP_KERNEL); + if (!spi) { + dev_err(dev, "cannot alloc spi_device\n"); + spi_master_put(master); + return NULL; + } + + spi->master = master; + spi->dev.parent = dev; + spi->dev.bus = &spi_bus_type; + spi->dev.release = spidev_release; + device_initialize(&spi->dev); + return spi; +} +EXPORT_SYMBOL_GPL(spi_alloc_device); + +/** + * spi_add_device - Add spi_device allocated with spi_alloc_device + * @spi: spi_device to register + * + * Companion function to spi_alloc_device. Devices allocated with + * spi_alloc_device can be added onto the spi bus with this function. + * + * Returns 0 on success; non-zero on failure + */ +int spi_add_device(struct spi_device *spi) +{ + struct device *dev = spi->master->dev.parent; + int status; + + /* Chipselects are numbered 0..max; validate. */ + if (spi->chip_select >= spi->master->num_chipselect) { + dev_err(dev, "cs%d >= max %d\n", + spi->chip_select, + spi->master->num_chipselect); + return -EINVAL; + } + + /* Set the bus ID string */ + snprintf(spi->dev.bus_id, sizeof spi->dev.bus_id, + "%s.%u", spi->master->dev.bus_id, + spi->chip_select); + + /* drivers may modify this initial i/o setup */ + status = spi->master->setup(spi); + if (status < 0) { + dev_err(dev, "can't %s %s, status %d\n", + "setup", spi->dev.bus_id, status); + return status; + } + + /* driver core catches callers that misbehave by defining + * devices that already exist. + */ + status = device_add(&spi->dev); + if (status < 0) { + dev_err(dev, "can't %s %s, status %d\n", + "add", spi->dev.bus_id, status); + return status; + } + + dev_dbg(dev, "registered child %s\n", spi->dev.bus_id); + return 0; +} +EXPORT_SYMBOL_GPL(spi_add_device); /** * spi_new_device - instantiate one new SPI device @@ -197,7 +287,6 @@ struct spi_device *spi_new_device(struct spi_master *master, struct spi_board_info *chip) { struct spi_device *proxy; - struct device *dev = master->dev.parent; int status; /* NOTE: caller did any chip->bus_num checks necessary. @@ -207,66 +296,28 @@ struct spi_device *spi_new_device(struct spi_master *master, * suggests syslogged diagnostics are best here (ugh). */ - /* Chipselects are numbered 0..max; validate. */ - if (chip->chip_select >= master->num_chipselect) { - dev_err(dev, "cs%d > max %d\n", - chip->chip_select, - master->num_chipselect); - return NULL; - } - - if (!spi_master_get(master)) + proxy = spi_alloc_device(master); + if (!proxy) return NULL; WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); - proxy = kzalloc(sizeof *proxy, GFP_KERNEL); - if (!proxy) { - dev_err(dev, "can't alloc dev for cs%d\n", - chip->chip_select); - goto fail; - } - proxy->master = master; proxy->chip_select = chip->chip_select; proxy->max_speed_hz = chip->max_speed_hz; proxy->mode = chip->mode; proxy->irq = chip->irq; strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); - - snprintf(proxy->dev.bus_id, sizeof proxy->dev.bus_id, - "%s.%u", master->dev.bus_id, - chip->chip_select); - proxy->dev.parent = dev; - proxy->dev.bus = &spi_bus_type; proxy->dev.platform_data = (void *) chip->platform_data; proxy->controller_data = chip->controller_data; proxy->controller_state = NULL; - proxy->dev.release = spidev_release; - /* drivers may modify this initial i/o setup */ - status = master->setup(proxy); + status = spi_add_device(proxy); if (status < 0) { - dev_err(dev, "can't %s %s, status %d\n", - "setup", proxy->dev.bus_id, status); - goto fail; + spi_dev_put(proxy); + return NULL; } - /* driver core catches callers that misbehave by defining - * devices that already exist. - */ - status = device_register(&proxy->dev); - if (status < 0) { - dev_err(dev, "can't %s %s, status %d\n", - "add", proxy->dev.bus_id, status); - goto fail; - } - dev_dbg(dev, "registered child %s\n", proxy->dev.bus_id); return proxy; - -fail: - spi_master_put(master); - kfree(proxy); - return NULL; } EXPORT_SYMBOL_GPL(spi_new_device); diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c index ec282aa92aaa..89da39f02d68 100644 --- a/drivers/spi/spi_s3c24xx.c +++ b/drivers/spi/spi_s3c24xx.c @@ -236,6 +236,19 @@ static irqreturn_t s3c24xx_spi_irq(int irq, void *dev) return IRQ_HANDLED; } +static void s3c24xx_spi_initialsetup(struct s3c24xx_spi *hw) +{ + /* for the moment, permanently enable the clock */ + + clk_enable(hw->clk); + + /* program defaults into the registers */ + + writeb(0xff, hw->regs + S3C2410_SPPRE); + writeb(SPPIN_DEFAULT, hw->regs + S3C2410_SPPIN); + writeb(SPCON_DEFAULT, hw->regs + S3C2410_SPCON); +} + static int __init s3c24xx_spi_probe(struct platform_device *pdev) { struct s3c2410_spi_info *pdata; @@ -270,6 +283,7 @@ static int __init s3c24xx_spi_probe(struct platform_device *pdev) /* setup the master state. */ master->num_chipselect = hw->pdata->num_cs; + master->bus_num = pdata->bus_num; /* setup the state for the bitbang driver */ @@ -326,15 +340,7 @@ static int __init s3c24xx_spi_probe(struct platform_device *pdev) goto err_no_clk; } - /* for the moment, permanently enable the clock */ - - clk_enable(hw->clk); - - /* program defaults into the registers */ - - writeb(0xff, hw->regs + S3C2410_SPPRE); - writeb(SPPIN_DEFAULT, hw->regs + S3C2410_SPPIN); - writeb(SPCON_DEFAULT, hw->regs + S3C2410_SPCON); + s3c24xx_spi_initialsetup(hw); /* setup any gpio we can */ @@ -414,7 +420,7 @@ static int s3c24xx_spi_resume(struct platform_device *pdev) { struct s3c24xx_spi *hw = platform_get_drvdata(pdev); - clk_enable(hw->clk); + s3c24xx_spi_initialsetup(hw); return 0; } |