diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mfd/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/mfd/Makefile | 1 | ||||
| -rw-r--r-- | drivers/mfd/ti-ssp.c | 476 | ||||
| -rw-r--r-- | drivers/spi/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/spi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/spi/ti-ssp-spi.c | 402 |
6 files changed, 901 insertions, 0 deletions
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index fd018366d67..0284c53c210 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -81,6 +81,17 @@ config MFD_DM355EVM_MSP boards. MSP430 firmware manages resets and power sequencing, inputs from buttons and the IR remote, LEDs, an RTC, and more. +config MFD_TI_SSP + tristate "TI Sequencer Serial Port support" + depends on ARCH_DAVINCI_TNETV107X + select MFD_CORE + ---help--- + Say Y here if you want support for the Sequencer Serial Port + in a Texas Instruments TNETV107X SoC. + + To compile this driver as a module, choose M here: the + module will be called ti-ssp. + config HTC_EGPIO bool "HTC EGPIO support" depends on GENERIC_HARDIRQS && GPIOLIB && ARM diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index a54e2c7c6a1..c56b6c7232e 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_HTC_I2CPLD) += htc-i2cpld.o obj-$(CONFIG_MFD_DAVINCI_VOICECODEC) += davinci_voicecodec.o obj-$(CONFIG_MFD_DM355EVM_MSP) += dm355evm_msp.o +obj-$(CONFIG_MFD_TI_SSP) += ti-ssp.o obj-$(CONFIG_MFD_STMPE) += stmpe.o obj-$(CONFIG_MFD_TC3589X) += tc3589x.o diff --git a/drivers/mfd/ti-ssp.c b/drivers/mfd/ti-ssp.c new file mode 100644 index 00000000000..af9ab0e5ca6 --- /dev/null +++ b/drivers/mfd/ti-ssp.c @@ -0,0 +1,476 @@ +/* + * Sequencer Serial Port (SSP) driver for Texas Instruments' SoCs + * + * Copyright (C) 2010 Texas Instruments Inc + * + * 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 + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/wait.h> +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/device.h> +#include <linux/spinlock.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/mfd/core.h> +#include <linux/mfd/ti_ssp.h> + +/* Register Offsets */ +#define REG_REV 0x00 +#define REG_IOSEL_1 0x04 +#define REG_IOSEL_2 0x08 +#define REG_PREDIV 0x0c +#define REG_INTR_ST 0x10 +#define REG_INTR_EN 0x14 +#define REG_TEST_CTRL 0x18 + +/* Per port registers */ +#define PORT_CFG_2 0x00 +#define PORT_ADDR 0x04 +#define PORT_DATA 0x08 +#define PORT_CFG_1 0x0c +#define PORT_STATE 0x10 + +#define SSP_PORT_CONFIG_MASK (SSP_EARLY_DIN | SSP_DELAY_DOUT) +#define SSP_PORT_CLKRATE_MASK 0x0f + +#define SSP_SEQRAM_WR_EN BIT(4) +#define SSP_SEQRAM_RD_EN BIT(5) +#define SSP_START BIT(15) +#define SSP_BUSY BIT(10) +#define SSP_PORT_ASL BIT(7) +#define SSP_PORT_CFO1 BIT(6) + +#define SSP_PORT_SEQRAM_SIZE 32 + +static const int ssp_port_base[] = {0x040, 0x080}; +static const int ssp_port_seqram[] = {0x100, 0x180}; + +struct ti_ssp { + struct resource *res; + struct device *dev; + void __iomem *regs; + spinlock_t lock; + struct clk *clk; + int irq; + wait_queue_head_t wqh; + + /* + * Some of the iosel2 register bits always read-back as 0, we need to + * remember these values so that we don't clobber previously set + * values. + */ + u32 iosel2; +}; + +static inline struct ti_ssp *dev_to_ssp(struct device *dev) +{ + return dev_get_drvdata(dev->parent); +} + +static inline int dev_to_port(struct device *dev) +{ + return to_platform_device(dev)->id; +} + +/* Register Access Helpers, rmw() functions need to run locked */ +static inline u32 ssp_read(struct ti_ssp *ssp, int reg) +{ + return __raw_readl(ssp->regs + reg); +} + +static inline void ssp_write(struct ti_ssp *ssp, int reg, u32 val) +{ + __raw_writel(val, ssp->regs + reg); +} + +static inline void ssp_rmw(struct ti_ssp *ssp, int reg, u32 mask, u32 bits) +{ + ssp_write(ssp, reg, (ssp_read(ssp, reg) & ~mask) | bits); +} + +static inline u32 ssp_port_read(struct ti_ssp *ssp, int port, int reg) +{ + return ssp_read(ssp, ssp_port_base[port] + reg); +} + +static inline void ssp_port_write(struct ti_ssp *ssp, int port, int reg, + u32 val) +{ + ssp_write(ssp, ssp_port_base[port] + reg, val); +} + +static inline void ssp_port_rmw(struct ti_ssp *ssp, int port, int reg, + u32 mask, u32 bits) +{ + ssp_rmw(ssp, ssp_port_base[port] + reg, mask, bits); +} + +static inline void ssp_port_clr_bits(struct ti_ssp *ssp, int port, int reg, + u32 bits) +{ + ssp_port_rmw(ssp, port, reg, bits, 0); +} + +static inline void ssp_port_set_bits(struct ti_ssp *ssp, int port, int reg, + u32 bits) +{ + ssp_port_rmw(ssp, port, reg, 0, bits); +} + +/* Called to setup port clock mode, caller must hold ssp->lock */ +static int __set_mode(struct ti_ssp *ssp, int port, int mode) +{ + mode &= SSP_PORT_CONFIG_MASK; + ssp_port_rmw(ssp, port, PORT_CFG_1, SSP_PORT_CONFIG_MASK, mode); + + return 0; +} + +int ti_ssp_set_mode(struct device *dev, int mode) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int ret; + + spin_lock(&ssp->lock); + ret = __set_mode(ssp, port, mode); + spin_unlock(&ssp->lock); + + return ret; +} +EXPORT_SYMBOL(ti_ssp_set_mode); + +/* Called to setup iosel2, caller must hold ssp->lock */ +static void __set_iosel2(struct ti_ssp *ssp, u32 mask, u32 val) +{ + ssp->iosel2 = (ssp->iosel2 & ~mask) | val; + ssp_write(ssp, REG_IOSEL_2, ssp->iosel2); +} + +/* Called to setup port iosel, caller must hold ssp->lock */ +static void __set_iosel(struct ti_ssp *ssp, int port, u32 iosel) +{ + unsigned val, shift = port ? 16 : 0; + + /* IOSEL1 gets the least significant 16 bits */ + val = ssp_read(ssp, REG_IOSEL_1); + val &= 0xffff << (port ? 0 : 16); + val |= (iosel & 0xffff) << (port ? 16 : 0); + ssp_write(ssp, REG_IOSEL_1, val); + + /* IOSEL2 gets the most significant 16 bits */ + val = (iosel >> 16) & 0x7; + __set_iosel2(ssp, 0x7 << shift, val << shift); +} + +int ti_ssp_set_iosel(struct device *dev, u32 iosel) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + + spin_lock(&ssp->lock); + __set_iosel(ssp, port, iosel); + spin_unlock(&ssp->lock); + + return 0; +} +EXPORT_SYMBOL(ti_ssp_set_iosel); + +int ti_ssp_load(struct device *dev, int offs, u32* prog, int len) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int i; + + if (len > SSP_PORT_SEQRAM_SIZE) + return -ENOSPC; + + spin_lock(&ssp->lock); + + /* Enable SeqRAM access */ + ssp_port_set_bits(ssp, port, PORT_CFG_2, SSP_SEQRAM_WR_EN); + + /* Copy code */ + for (i = 0; i < len; i++) { + __raw_writel(prog[i], ssp->regs + offs + 4*i + + ssp_port_seqram[port]); + } + + /* Disable SeqRAM access */ + ssp_port_clr_bits(ssp, port, PORT_CFG_2, SSP_SEQRAM_WR_EN); + + spin_unlock(&ssp->lock); + + return 0; +} +EXPORT_SYMBOL(ti_ssp_load); + +int ti_ssp_raw_read(struct device *dev) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int shift = port ? 27 : 11; + + return (ssp_read(ssp, REG_IOSEL_2) >> shift) & 0xf; +} +EXPORT_SYMBOL(ti_ssp_raw_read); + +int ti_ssp_raw_write(struct device *dev, u32 val) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev), shift; + + spin_lock(&ssp->lock); + + shift = port ? 22 : 6; + val &= 0xf; + __set_iosel2(ssp, 0xf << shift, val << shift); + + spin_unlock(&ssp->lock); + + return 0; +} +EXPORT_SYMBOL(ti_ssp_raw_write); + +static inline int __xfer_done(struct ti_ssp *ssp, int port) +{ + return !(ssp_port_read(ssp, port, PORT_CFG_1) & SSP_BUSY); +} + +int ti_ssp_run(struct device *dev, u32 pc, u32 input, u32 *output) +{ + struct ti_ssp *ssp = dev_to_ssp(dev); + int port = dev_to_port(dev); + int ret; + + if (pc & ~(0x3f)) + return -EINVAL; + + /* Grab ssp->lock to serialize rmw on ssp registers */ + spin_lock(&ssp->lock); + + ssp_port_write(ssp, port, PORT_ADDR, input >> 16); + ssp_port_write(ssp, port, PORT_DATA, input & 0xffff); + ssp_port_rmw(ssp, port, PORT_CFG_1, 0x3f, pc); + + /* grab wait queue head lock to avoid race with the isr */ + spin_lock_irq(&ssp->wqh.lock); + + /* kick off sequence execution in hardware */ + ssp_port_set_bits(ssp, port, PORT_CFG_1, SSP_START); + + /* drop ssp lock; no register writes beyond this */ + spin_unlock(&ssp->lock); + + ret = wait_event_interruptible_locked_irq(ssp->wqh, + __xfer_done(ssp, port)); + spin_unlock_irq(&ssp->wqh.lock); + + if (ret < 0) + return ret; + + if (output) { + *output = (ssp_port_read(ssp, port, PORT_ADDR) << 16) | + (ssp_port_read(ssp, port, PORT_DATA) & 0xffff); + } + + ret = ssp_port_read(ssp, port, PORT_STATE) & 0x3f; /* stop address */ + + return ret; +} +EXPORT_SYMBOL(ti_ssp_run); + +static irqreturn_t ti_ssp_interrupt(int irq, void *dev_data) +{ + struct ti_ssp *ssp = dev_data; + + spin_lock(&ssp->wqh.lock); + + ssp_write(ssp, REG_INTR_ST, 0x3); + wake_up_locked(&ssp->wqh); + + spin_unlock(&ssp->wqh.lock); + + return IRQ_HANDLED; +} + +static int __devinit ti_ssp_probe(struct platform_device *pdev) +{ + static struct ti_ssp *ssp; + const struct ti_ssp_data *pdata = pdev->dev.platform_data; + int error = 0, prediv = 0xff, id; + unsigned long sysclk; + struct device *dev = &pdev->dev; + struct mfd_cell cells[2]; + + ssp = kzalloc(sizeof(*ssp), GFP_KERNEL); + if (!ssp) { + dev_err(dev, "cannot allocate device info\n"); + return -ENOMEM; + } + + ssp->dev = dev; + dev_set_drvdata(dev, ssp); + + ssp->res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!ssp->res) { + error = -ENODEV; + dev_err(dev, "cannot determine register area\n"); + goto error_res; + } + + if (!request_mem_region(ssp->res->start, resource_size(ssp->res), + pdev->name)) { + error = -ENOMEM; + dev_err(dev, "cannot claim register memory\n"); + goto error_res; + } + + ssp->regs = ioremap(ssp->res->start, resource_size(ssp->res)); + if (!ssp->regs) { + error = -ENOMEM; + dev_err(dev, "cannot map register memory\n"); + goto error_map; + } + + ssp->clk = clk_get(dev, NULL); + if (IS_ERR(ssp->clk)) { + error = PTR_ERR(ssp->clk); + dev_err(dev, "cannot claim device clock\n"); + goto error_clk; + } + + ssp->irq = platform_get_irq(pdev, 0); + if (ssp->irq < 0) { + error = -ENODEV; + dev_err(dev, "unknown irq\n"); + goto error_irq; + } + + error = request_threaded_irq(ssp->irq, NULL, ti_ssp_interrupt, 0, + dev_name(dev), ssp); + if (error < 0) { + dev_err(dev, "cannot acquire irq\n"); + goto error_irq; + } + + spin_lock_init(&ssp->lock); + init_waitqueue_head(&ssp->wqh); + + /* Power on and initialize SSP */ + error = clk_enable(ssp->clk); + if (error) { + dev_err(dev, "cannot enable device clock\n"); + goto error_enable; + } + + /* Reset registers to a sensible known state */ + ssp_write(ssp, REG_IOSEL_1, 0); + ssp_write(ssp, REG_IOSEL_2, 0); + ssp_write(ssp, REG_INTR_EN, 0x3); + ssp_write(ssp, REG_INTR_ST, 0x3); + ssp_write(ssp, REG_TEST_CTRL, 0); + ssp_port_write(ssp, 0, PORT_CFG_1, SSP_PORT_ASL); + ssp_port_write(ssp, 1, PORT_CFG_1, SSP_PORT_ASL); + ssp_port_write(ssp, 0, PORT_CFG_2, SSP_PORT_CFO1); + ssp_port_write(ssp, 1, PORT_CFG_2, SSP_PORT_CFO1); + + sysclk = clk_get_rate(ssp->clk); + if (pdata && pdata->out_clock) + prediv = (sysclk / pdata->out_clock) - 1; + prediv = clamp(prediv, 0, 0xff); + ssp_rmw(ssp, REG_PREDIV, 0xff, prediv); + + memset(cells, 0, sizeof(cells)); + for (id = 0; id < 2; id++) { + const struct ti_ssp_dev_data *data = &pdata->dev_data[id]; + + cells[id].id = id; + cells[id].name = data->dev_name; + cells[id].platform_data = data->pdata; + cells[id].data_size = data->pdata_size; + } + + error = mfd_add_devices(dev, 0, cells, 2, NULL, 0); + if (error < 0) { + dev_err(dev, "cannot add mfd cells\n"); + goto error_enable; + } + + return 0; + +error_enable: + free_irq(ssp->irq, ssp); +error_irq: + clk_put(ssp->clk); +error_clk: + iounmap(ssp->regs); +error_map: + release_mem_region(ssp->res->start, resource_size(ssp->res)); +error_res: + kfree(ssp); + return error; +} + +static int __devexit ti_ssp_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct ti_ssp *ssp = dev_get_drvdata(dev); + + mfd_remove_devices(dev); + clk_disable(ssp->clk); + free_irq(ssp->irq, ssp); + clk_put(ssp->clk); + iounmap(ssp->regs); + release_mem_region(ssp->res->start, resource_size(ssp->res)); + kfree(ssp); + dev_set_drvdata(dev, NULL); + return 0; +} + +static struct platform_driver ti_ssp_driver = { + .probe = ti_ssp_probe, + .remove = __devexit_p(ti_ssp_remove), + .driver = { + .name = "ti-ssp", + .owner = THIS_MODULE, + } +}; + +static int __init ti_ssp_init(void) +{ + return platform_driver_register(&ti_ssp_driver); +} +module_init(ti_ssp_init); + +static void __exit ti_ssp_exit(void) +{ + platform_driver_unregister(&ti_ssp_driver); +} +module_exit(ti_ssp_exit); + +MODULE_DESCRIPTION("Sequencer Serial Port (SSP) Driver"); +MODULE_AUTHOR("Cyril Chemparathy"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ti-ssp"); diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 996cf035938..7b90fc361b5 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -350,6 +350,16 @@ config SPI_TEGRA help SPI driver for NVidia Tegra SoCs +config SPI_TI_SSP + tristate "TI Sequencer Serial Port - SPI Support" + depends on MFD_TI_SSP + help + This selects an SPI master implementation using a TI sequencer + serial port. + + To compile this driver as a module, choose M here: the + module will be called ti-ssp-spi. + config SPI_TOPCLIFF_PCH tristate "Topcliff PCH SPI Controller" depends on PCI diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 86d1b5f9bbd..f3f31d98835 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -43,6 +43,7 @@ obj-$(CONFIG_SPI_S3C24XX_GPIO) += spi_s3c24xx_gpio.o obj-$(CONFIG_SPI_S3C24XX) += spi_s3c24xx_hw.o obj-$(CONFIG_SPI_S3C64XX) += spi_s3c64xx.o obj-$(CONFIG_SPI_TEGRA) += spi_tegra.o +obj-$(CONFIG_SPI_TI_SSP) += ti-ssp-spi.o obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi_topcliff_pch.o obj-$(CONFIG_SPI_TXX9) += spi_txx9.o obj-$(CONFIG_SPI_XILINX) += xilinx_spi.o diff --git a/drivers/spi/ti-ssp-spi.c b/drivers/spi/ti-ssp-spi.c new file mode 100644 index 00000000000..ee22795c797 --- /dev/null +++ b/drivers/spi/ti-ssp-spi.c @@ -0,0 +1,402 @@ +/* + * Sequencer Serial Port (SSP) based SPI master driver + * + * Copyright (C) 2010 Texas Instruments Inc + * + * 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 + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/mfd/ti_ssp.h> + +#define MODE_BITS (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH) + +struct ti_ssp_spi { + struct spi_master *master; + struct device *dev; + spinlock_t lock; + struct list_head msg_queue; + struct completion complete; + bool shutdown; + struct workqueue_struct *workqueue; + struct work_struct work; + u8 mode, bpw; + int cs_active; + u32 pc_en, pc_dis, pc_wr, pc_rd; + void (*select)(int cs); +}; + +static u32 ti_ssp_spi_rx(struct ti_ssp_spi *hw) +{ + u32 ret; + + ti_ssp_run(hw->dev, hw->pc_rd, 0, &ret); + return ret; +} + +static void ti_ssp_spi_tx(struct ti_ssp_spi *hw, u32 data) +{ + ti_ssp_run(hw->dev, hw->pc_wr, data << (32 - hw->bpw), NULL); +} + +static int ti_ssp_spi_txrx(struct ti_ssp_spi *hw, struct spi_message *msg, + struct spi_transfer *t) +{ + int count; + + if (hw->bpw <= 8) { + u8 *rx = t->rx_buf; + const u8 *tx = t->tx_buf; + + for (count = 0; count < t->len; count += 1) { + if (t->tx_buf) + ti_ssp_spi_tx(hw, *tx++); + if (t->rx_buf) + *rx++ = ti_ssp_spi_rx(hw); + } + } else if (hw->bpw <= 16) { + u16 *rx = t->rx_buf; + const u16 *tx = t->tx_buf; + + for (count = 0; count < t->len; count += 2) { + if (t->tx_buf) + ti_ssp_spi_tx(hw, *tx++); + if (t->rx_buf) + *rx++ = ti_ssp_spi_rx(hw); + } + } else { + u32 *rx = t->rx_buf; + const u32 *tx = t->tx_buf; + + for (count = 0; count < t->len; count += 4) { + if (t->tx_buf) + ti_ssp_spi_tx(hw, *tx++); + if (t->rx_buf) + *rx++ = ti_ssp_spi_rx(hw); + } + } + + msg->actual_length += count; /* bytes transferred */ + + dev_dbg(&msg->spi->dev, "xfer %s%s, %d bytes, %d bpw, count %d%s\n", + t->tx_buf ? "tx" : "", t->rx_buf ? "rx" : "", t->len, + hw->bpw, count, (count < t->len) ? " (under)" : ""); + + return (count < t->len) ? -EIO : 0; /* left over data */ +} + +static void ti_ssp_spi_chip_select(struct ti_ssp_spi *hw, int cs_active) +{ + cs_active = !!cs_active; + if (cs_active == hw->cs_active) + return; + ti_ssp_run(hw->dev, cs_active ? hw->pc_en : hw->pc_dis, 0, NULL); + hw->cs_active = cs_active; +} + +#define __SHIFT_OUT(bits) (SSP_OPCODE_SHIFT | SSP_OUT_MODE | \ + cs_en | clk | SSP_COUNT((bits) * 2 - 1)) +#define __SHIFT_IN(bits) (SSP_OPCODE_SHIFT | SSP_IN_MODE | \ + cs_en | clk | SSP_COUNT((bits) * 2 - 1)) + +static int ti_ssp_spi_setup_transfer(struct ti_ssp_spi *hw, u8 bpw, u8 mode) +{ + int error, idx = 0; + u32 seqram[16]; + u32 cs_en, cs_dis, clk; + u32 topbits, botbits; + + mode &= MODE_BITS; + if (mode == hw->mode && bpw == hw->bpw) + return 0; + + cs_en = (mode & SPI_CS_HIGH) ? SSP_CS_HIGH : SSP_CS_LOW; + cs_dis = (mode & SPI_CS_HIGH) ? SSP_CS_LOW : SSP_CS_HIGH; + clk = (mode & SPI_CPOL) ? SSP_CLK_HIGH : SSP_CLK_LOW; + + /* Construct instructions */ + + /* Disable Chip Select */ + hw->pc_dis = idx; + seqram[idx++] = SSP_OPCODE_DIRECT | SSP_OUT_MODE | cs_dis | clk; + seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_dis | clk; + + /* Enable Chip Select */ + hw->pc_en = idx; + seqram[idx++] = SSP_OPCODE_DIRECT | SSP_OUT_MODE | cs_en | clk; + seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk; + + /* Reads and writes need to be split for bpw > 16 */ + topbits = (bpw > 16) ? 16 : bpw; + botbits = bpw - topbits; + + /* Write */ + hw->pc_wr = idx; + seqram[idx++] = __SHIFT_OUT(topbits) | SSP_ADDR_REG; + if (botbits) + seqram[idx++] = __SHIFT_OUT(botbits) | SSP_DATA_REG; + seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk; + + /* Read */ + hw->pc_rd = idx; + if (botbits) + seqram[idx++] = __SHIFT_IN(botbits) | SSP_ADDR_REG; + seqram[idx++] = __SHIFT_IN(topbits) | SSP_DATA_REG; + seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk; + + error = ti_ssp_load(hw->dev, 0, seqram, idx); + if (error < 0) + return error; + + error = ti_ssp_set_mode(hw->dev, ((mode & SPI_CPHA) ? + 0 : SSP_EARLY_DIN)); + if (error < 0) + return error; + + hw->bpw = bpw; + hw->mode = mode; + + return error; +} + +static void ti_ssp_spi_work(struct work_struct *work) +{ + struct ti_ssp_spi *hw = container_of(work, struct ti_ssp_spi, work); + + spin_lock(&hw->lock); + + while (!list_empty(&hw->msg_queue)) { + struct spi_message *m; + struct spi_device *spi; + struct spi_transfer *t = NULL; + int status = 0; + + m = container_of(hw->msg_queue.next, struct spi_message, + queue); + + list_del_init(&m->queue); + + spin_unlock(&hw->lock); + + spi = m->spi; + + if (hw->select) + hw->select(spi->chip_select); + + list_for_each_entry(t, &m->transfers, transfer_list) { + int bpw = spi->bits_per_word; + int xfer_status; + + if (t->bits_per_word) + bpw = t->bits_per_word; + + if (ti_ssp_spi_setup_transfer(hw, bpw, spi->mode) < 0) + break; + + ti_ssp_spi_chip_select(hw, 1); + + xfer_status = ti_ssp_spi_txrx(hw, m, t); + if (xfer_status < 0) + status = xfer_status; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (t->cs_change) + ti_ssp_spi_chip_select(hw, 0); + } + + ti_ssp_spi_chip_select(hw, 0); + m->status = status; + m->complete(m->context); + + spin_lock(&hw->lock); + } + + if (hw->shutdown) + complete(&hw->complete); + + spin_unlock(&hw->lock); +} + +static int ti_ssp_spi_setup(struct spi_device *spi) +{ + if (spi->bits_per_word > 32) + return -EINVAL; + + return 0; +} + +static int ti_ssp_spi_transfer(struct spi_device *spi, struct spi_message *m) +{ + struct ti_ssp_spi *hw; + struct spi_transfer *t; + int error = 0; + + m->actual_length = 0; + m->status = -EINPROGRESS; + + hw = spi_master_get_devdata(spi->master); + + if (list_empty(&m->transfers) || !m->complete) + return -EINVAL; + + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->len && !(t->rx_buf || t->tx_buf)) { + dev_err(&spi->dev, "invalid xfer, no buffer\n"); + return -EINVAL; + } + + if (t->len && t->rx_buf && t->tx_buf) { + dev_err(&spi->dev, "invalid xfer, full duplex\n"); + return -EINVAL; + } + + if (t->bits_per_word > 32) { + dev_err(&spi->dev, "invalid xfer width %d\n", + t->bits_per_word); + return -EINVAL; + } + } + + spin_lock(&hw->lock); + if (hw->shutdown) { + error = -ESHUTDOWN; + goto error_unlock; + } + list_add_tail(&m->queue, &hw->msg_queue); + queue_work(hw->workqueue, &hw->work); +error_unlock: + spin_unlock(&hw->lock); + return error; +} + +static int __devinit ti_ssp_spi_probe(struct platform_device *pdev) +{ + const struct ti_ssp_spi_data *pdata; + struct ti_ssp_spi *hw; + struct spi_master *master; + struct device *dev = &pdev->dev; + int error = 0; + + pdata = dev->platform_data; + if (!pdata) { + dev_err(dev, "platform data not found\n"); + return -EINVAL; + } + + master = spi_alloc_master(dev, sizeof(struct ti_ssp_spi)); + if (!master) { + dev_err(dev, "cannot allocate SPI master\n"); + return -ENOMEM; + } + + hw = spi_master_get_devdata(master); + platform_set_drvdata(pdev, hw); + + hw->master = master; + hw->dev = dev; + hw->select = pdata->select; + + spin_lock_init(&hw->lock); + init_completion(&hw->complete); + INIT_LIST_HEAD(&hw->msg_queue); + INIT_WORK(&hw->work, ti_ssp_spi_work); + + hw->workqueue = create_singlethread_workqueue(dev_name(dev)); + if (!hw->workqueue) { + error = -ENOMEM; + dev_err(dev, "work queue creation failed\n"); + goto error_wq; + } + + error = ti_ssp_set_iosel(hw->dev, pdata->iosel); + if (error < 0) { + dev_err(dev, "io setup failed\n"); + goto error_iosel; + } + + master->bus_num = pdev->id; + master->num_chipselect = pdata->num_cs; + master->mode_bits = MODE_BITS; + master->flags = SPI_MASTER_HALF_DUPLEX; + master->setup = ti_ssp_spi_setup; + master->transfer = ti_ssp_spi_transfer; + + error = spi_register_master(master); + if (error) { + dev_err(dev, "master registration failed\n"); + goto error_reg; + } + + return 0; + +error_reg: +error_iosel: + destroy_workqueue(hw->workqueue); +error_wq: + spi_master_put(master); + return error; +} + +static int __devexit ti_ssp_spi_remove(struct platform_device *pdev) +{ + struct ti_ssp_spi *hw = platform_get_drvdata(pdev); + int error; + + hw->shutdown = 1; + while (!list_empty(&hw->msg_queue)) { + error = wait_for_completion_interruptible(&hw->complete); + if (error < 0) { + hw->shutdown = 0; + return error; + } + } + destroy_workqueue(hw->workqueue); + spi_unregister_master(hw->master); + + return 0; +} + +static struct platform_driver ti_ssp_spi_driver = { + .probe = ti_ssp_spi_probe, + .remove = __devexit_p(ti_ssp_spi_remove), + .driver = { + .name = "ti-ssp-spi", + .owner = THIS_MODULE, + }, +}; + +static int __init ti_ssp_spi_init(void) +{ + return platform_driver_register(&ti_ssp_spi_driver); +} +module_init(ti_ssp_spi_init); + +static void __exit ti_ssp_spi_exit(void) +{ + platform_driver_unregister(&ti_ssp_spi_driver); +} +module_exit(ti_ssp_spi_exit); + +MODULE_DESCRIPTION("SSP SPI Master"); +MODULE_AUTHOR("Cyril Chemparathy"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ti-ssp-spi"); |