diff options
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/Kconfig | 7 | ||||
-rw-r--r-- | drivers/spi/Makefile | 1 | ||||
-rw-r--r-- | drivers/spi/spi_imx.c | 1770 |
3 files changed, 0 insertions, 1778 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 2c733c2..86056d14 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -116,13 +116,6 @@ config SPI_GPIO GPIO operations, you should be able to leverage that for better speed with a custom version of this driver; see the source code. -config SPI_IMX - tristate "Freescale iMX SPI controller" - depends on ARCH_MX1 && EXPERIMENTAL - help - This enables using the Freescale iMX SPI controller in master - mode. - config SPI_LM70_LLP tristate "Parallel port adapter for LM70 eval board (DEVELOPMENT)" depends on PARPORT && EXPERIMENTAL diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 3de408d..0f20a70b 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -17,7 +17,6 @@ obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o obj-$(CONFIG_SPI_AU1550) += au1550_spi.o obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o obj-$(CONFIG_SPI_GPIO) += spi_gpio.o -obj-$(CONFIG_SPI_IMX) += spi_imx.o obj-$(CONFIG_SPI_LM70_LLP) += spi_lm70llp.o obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o obj-$(CONFIG_SPI_OMAP_UWIRE) += omap_uwire.o diff --git a/drivers/spi/spi_imx.c b/drivers/spi/spi_imx.c deleted file mode 100644 index c195e45..0000000 --- a/drivers/spi/spi_imx.c +++ /dev/null @@ -1,1770 +0,0 @@ -/* - * drivers/spi/spi_imx.c - * - * Copyright (C) 2006 SWAPP - * Andrea Paterniani <a.paterniani@swapp-eng.it> - * - * Initial version inspired by: - * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c - * - * 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. - */ - -#include <linux/init.h> -#include <linux/module.h> -#include <linux/device.h> -#include <linux/ioport.h> -#include <linux/errno.h> -#include <linux/interrupt.h> -#include <linux/platform_device.h> -#include <linux/dma-mapping.h> -#include <linux/spi/spi.h> -#include <linux/workqueue.h> -#include <linux/delay.h> -#include <linux/clk.h> - -#include <asm/io.h> -#include <asm/irq.h> -#include <asm/delay.h> - -#include <mach/hardware.h> -#include <mach/imx-dma.h> -#include <mach/spi_imx.h> - -/*-------------------------------------------------------------------------*/ -/* SPI Registers offsets from peripheral base address */ -#define SPI_RXDATA (0x00) -#define SPI_TXDATA (0x04) -#define SPI_CONTROL (0x08) -#define SPI_INT_STATUS (0x0C) -#define SPI_TEST (0x10) -#define SPI_PERIOD (0x14) -#define SPI_DMA (0x18) -#define SPI_RESET (0x1C) - -/* SPI Control Register Bit Fields & Masks */ -#define SPI_CONTROL_BITCOUNT_MASK (0xF) /* Bit Count Mask */ -#define SPI_CONTROL_BITCOUNT(n) (((n) - 1) & SPI_CONTROL_BITCOUNT_MASK) -#define SPI_CONTROL_POL (0x1 << 4) /* Clock Polarity Mask */ -#define SPI_CONTROL_POL_ACT_HIGH (0x0 << 4) /* Active high pol. (0=idle) */ -#define SPI_CONTROL_POL_ACT_LOW (0x1 << 4) /* Active low pol. (1=idle) */ -#define SPI_CONTROL_PHA (0x1 << 5) /* Clock Phase Mask */ -#define SPI_CONTROL_PHA_0 (0x0 << 5) /* Clock Phase 0 */ -#define SPI_CONTROL_PHA_1 (0x1 << 5) /* Clock Phase 1 */ -#define SPI_CONTROL_SSCTL (0x1 << 6) /* /SS Waveform Select Mask */ -#define SPI_CONTROL_SSCTL_0 (0x0 << 6) /* Master: /SS stays low between SPI burst - Slave: RXFIFO advanced by BIT_COUNT */ -#define SPI_CONTROL_SSCTL_1 (0x1 << 6) /* Master: /SS insert pulse between SPI burst - Slave: RXFIFO advanced by /SS rising edge */ -#define SPI_CONTROL_SSPOL (0x1 << 7) /* /SS Polarity Select Mask */ -#define SPI_CONTROL_SSPOL_ACT_LOW (0x0 << 7) /* /SS Active low */ -#define SPI_CONTROL_SSPOL_ACT_HIGH (0x1 << 7) /* /SS Active high */ -#define SPI_CONTROL_XCH (0x1 << 8) /* Exchange */ -#define SPI_CONTROL_SPIEN (0x1 << 9) /* SPI Module Enable */ -#define SPI_CONTROL_MODE (0x1 << 10) /* SPI Mode Select Mask */ -#define SPI_CONTROL_MODE_SLAVE (0x0 << 10) /* SPI Mode Slave */ -#define SPI_CONTROL_MODE_MASTER (0x1 << 10) /* SPI Mode Master */ -#define SPI_CONTROL_DRCTL (0x3 << 11) /* /SPI_RDY Control Mask */ -#define SPI_CONTROL_DRCTL_0 (0x0 << 11) /* Ignore /SPI_RDY */ -#define SPI_CONTROL_DRCTL_1 (0x1 << 11) /* /SPI_RDY falling edge triggers input */ -#define SPI_CONTROL_DRCTL_2 (0x2 << 11) /* /SPI_RDY active low level triggers input */ -#define SPI_CONTROL_DATARATE (0x7 << 13) /* Data Rate Mask */ -#define SPI_PERCLK2_DIV_MIN (0) /* PERCLK2:4 */ -#define SPI_PERCLK2_DIV_MAX (7) /* PERCLK2:512 */ -#define SPI_CONTROL_DATARATE_MIN (SPI_PERCLK2_DIV_MAX << 13) -#define SPI_CONTROL_DATARATE_MAX (SPI_PERCLK2_DIV_MIN << 13) -#define SPI_CONTROL_DATARATE_BAD (SPI_CONTROL_DATARATE_MIN + 1) - -/* SPI Interrupt/Status Register Bit Fields & Masks */ -#define SPI_STATUS_TE (0x1 << 0) /* TXFIFO Empty Status */ -#define SPI_STATUS_TH (0x1 << 1) /* TXFIFO Half Status */ -#define SPI_STATUS_TF (0x1 << 2) /* TXFIFO Full Status */ -#define SPI_STATUS_RR (0x1 << 3) /* RXFIFO Data Ready Status */ -#define SPI_STATUS_RH (0x1 << 4) /* RXFIFO Half Status */ -#define SPI_STATUS_RF (0x1 << 5) /* RXFIFO Full Status */ -#define SPI_STATUS_RO (0x1 << 6) /* RXFIFO Overflow */ -#define SPI_STATUS_BO (0x1 << 7) /* Bit Count Overflow */ -#define SPI_STATUS (0xFF) /* SPI Status Mask */ -#define SPI_INTEN_TE (0x1 << 8) /* TXFIFO Empty Interrupt Enable */ -#define SPI_INTEN_TH (0x1 << 9) /* TXFIFO Half Interrupt Enable */ -#define SPI_INTEN_TF (0x1 << 10) /* TXFIFO Full Interrupt Enable */ -#define SPI_INTEN_RE (0x1 << 11) /* RXFIFO Data Ready Interrupt Enable */ -#define SPI_INTEN_RH (0x1 << 12) /* RXFIFO Half Interrupt Enable */ -#define SPI_INTEN_RF (0x1 << 13) /* RXFIFO Full Interrupt Enable */ -#define SPI_INTEN_RO (0x1 << 14) /* RXFIFO Overflow Interrupt Enable */ -#define SPI_INTEN_BO (0x1 << 15) /* Bit Count Overflow Interrupt Enable */ -#define SPI_INTEN (0xFF << 8) /* SPI Interrupt Enable Mask */ - -/* SPI Test Register Bit Fields & Masks */ -#define SPI_TEST_TXCNT (0xF << 0) /* TXFIFO Counter */ -#define SPI_TEST_RXCNT_LSB (4) /* RXFIFO Counter LSB */ -#define SPI_TEST_RXCNT (0xF << 4) /* RXFIFO Counter */ -#define SPI_TEST_SSTATUS (0xF << 8) /* State Machine Status */ -#define SPI_TEST_LBC (0x1 << 14) /* Loop Back Control */ - -/* SPI Period Register Bit Fields & Masks */ -#define SPI_PERIOD_WAIT (0x7FFF << 0) /* Wait Between Transactions */ -#define SPI_PERIOD_MAX_WAIT (0x7FFF) /* Max Wait Between - Transactions */ -#define SPI_PERIOD_CSRC (0x1 << 15) /* Period Clock Source Mask */ -#define SPI_PERIOD_CSRC_BCLK (0x0 << 15) /* Period Clock Source is - Bit Clock */ -#define SPI_PERIOD_CSRC_32768 (0x1 << 15) /* Period Clock Source is - 32.768 KHz Clock */ - -/* SPI DMA Register Bit Fields & Masks */ -#define SPI_DMA_RHDMA (0x1 << 4) /* RXFIFO Half Status */ -#define SPI_DMA_RFDMA (0x1 << 5) /* RXFIFO Full Status */ -#define SPI_DMA_TEDMA (0x1 << 6) /* TXFIFO Empty Status */ -#define SPI_DMA_THDMA (0x1 << 7) /* TXFIFO Half Status */ -#define SPI_DMA_RHDEN (0x1 << 12) /* RXFIFO Half DMA Request Enable */ -#define SPI_DMA_RFDEN (0x1 << 13) /* RXFIFO Full DMA Request Enable */ -#define SPI_DMA_TEDEN (0x1 << 14) /* TXFIFO Empty DMA Request Enable */ -#define SPI_DMA_THDEN (0x1 << 15) /* TXFIFO Half DMA Request Enable */ - -/* SPI Soft Reset Register Bit Fields & Masks */ -#define SPI_RESET_START (0x1) /* Start */ - -/* Default SPI configuration values */ -#define SPI_DEFAULT_CONTROL \ -( \ - SPI_CONTROL_BITCOUNT(16) | \ - SPI_CONTROL_POL_ACT_HIGH | \ - SPI_CONTROL_PHA_0 | \ - SPI_CONTROL_SPIEN | \ - SPI_CONTROL_SSCTL_1 | \ - SPI_CONTROL_MODE_MASTER | \ - SPI_CONTROL_DRCTL_0 | \ - SPI_CONTROL_DATARATE_MIN \ -) -#define SPI_DEFAULT_ENABLE_LOOPBACK (0) -#define SPI_DEFAULT_ENABLE_DMA (0) -#define SPI_DEFAULT_PERIOD_WAIT (8) -/*-------------------------------------------------------------------------*/ - - -/*-------------------------------------------------------------------------*/ -/* TX/RX SPI FIFO size */ -#define SPI_FIFO_DEPTH (8) -#define SPI_FIFO_BYTE_WIDTH (2) -#define SPI_FIFO_OVERFLOW_MARGIN (2) - -/* DMA burst length for half full/empty request trigger */ -#define SPI_DMA_BLR (SPI_FIFO_DEPTH * SPI_FIFO_BYTE_WIDTH / 2) - -/* Dummy char output to achieve reads. - Choosing something different from all zeroes may help pattern recogition - for oscilloscope analysis, but may break some drivers. */ -#define SPI_DUMMY_u8 0 -#define SPI_DUMMY_u16 ((SPI_DUMMY_u8 << 8) | SPI_DUMMY_u8) -#define SPI_DUMMY_u32 ((SPI_DUMMY_u16 << 16) | SPI_DUMMY_u16) - -/** - * Macro to change a u32 field: - * @r : register to edit - * @m : bit mask - * @v : new value for the field correctly bit-alligned -*/ -#define u32_EDIT(r, m, v) r = (r & ~(m)) | (v) - -/* Message state */ -#define START_STATE ((void*)0) -#define RUNNING_STATE ((void*)1) -#define DONE_STATE ((void*)2) -#define ERROR_STATE ((void*)-1) - -/* Queue state */ -#define QUEUE_RUNNING (0) -#define QUEUE_STOPPED (1) - -#define IS_DMA_ALIGNED(x) (((u32)(x) & 0x03) == 0) -#define DMA_ALIGNMENT 4 -/*-------------------------------------------------------------------------*/ - - -/*-------------------------------------------------------------------------*/ -/* Driver data structs */ - -/* Context */ -struct driver_data { - /* Driver model hookup */ - struct platform_device *pdev; - - /* SPI framework hookup */ - struct spi_master *master; - - /* IMX hookup */ - struct spi_imx_master *master_info; - - /* Memory resources and SPI regs virtual address */ - struct resource *ioarea; - void __iomem *regs; - - /* SPI RX_DATA physical address */ - dma_addr_t rd_data_phys; - - /* Driver message queue */ - struct workqueue_struct *workqueue; - struct work_struct work; - spinlock_t lock; - struct list_head queue; - int busy; - int run; - - /* Message Transfer pump */ - struct tasklet_struct pump_transfers; - - /* Current message, transfer and state */ - struct spi_message *cur_msg; - struct spi_transfer *cur_transfer; - struct chip_data *cur_chip; - - /* Rd / Wr buffers pointers */ - size_t len; - void *tx; - void *tx_end; - void *rx; - void *rx_end; - - u8 rd_only; - u8 n_bytes; - int cs_change; - - /* Function pointers */ - irqreturn_t (*transfer_handler)(struct driver_data *drv_data); - void (*cs_control)(u32 command); - - /* DMA setup */ - int rx_channel; - int tx_channel; - dma_addr_t rx_dma; - dma_addr_t tx_dma; - int rx_dma_needs_unmap; - int tx_dma_needs_unmap; - size_t tx_map_len; - u32 dummy_dma_buf ____cacheline_aligned; - - struct clk *clk; -}; - -/* Runtime state */ -struct chip_data { - u32 control; - u32 period; - u32 test; - - u8 enable_dma:1; - u8 bits_per_word; - u8 n_bytes; - u32 max_speed_hz; - - void (*cs_control)(u32 command); -}; -/*-------------------------------------------------------------------------*/ - - -static void pump_messages(struct work_struct *work); - -static void flush(struct driver_data *drv_data) -{ - void __iomem *regs = drv_data->regs; - u32 control; - - dev_dbg(&drv_data->pdev->dev, "flush\n"); - - /* Wait for end of transaction */ - do { - control = readl(regs + SPI_CONTROL); - } while (control & SPI_CONTROL_XCH); - - /* Release chip select if requested, transfer delays are - handled in pump_transfers */ - if (drv_data->cs_change) - drv_data->cs_control(SPI_CS_DEASSERT); - - /* Disable SPI to flush FIFOs */ - writel(control & ~SPI_CONTROL_SPIEN, regs + SPI_CONTROL); - writel(control, regs + SPI_CONTROL); -} - -static void restore_state(struct driver_data *drv_data) -{ - void __iomem *regs = drv_data->regs; - struct chip_data *chip = drv_data->cur_chip; - - /* Load chip registers */ - dev_dbg(&drv_data->pdev->dev, - "restore_state\n" - " test = 0x%08X\n" - " control = 0x%08X\n", - chip->test, - chip->control); - writel(chip->test, regs + SPI_TEST); - writel(chip->period, regs + SPI_PERIOD); - writel(0, regs + SPI_INT_STATUS); - writel(chip->control, regs + SPI_CONTROL); -} - -static void null_cs_control(u32 command) -{ -} - -static inline u32 data_to_write(struct driver_data *drv_data) -{ - return ((u32)(drv_data->tx_end - drv_data->tx)) / drv_data->n_bytes; -} - -static inline u32 data_to_read(struct driver_data *drv_data) -{ - return ((u32)(drv_data->rx_end - drv_data->rx)) / drv_data->n_bytes; -} - -static int write(struct driver_data *drv_data) -{ - void __iomem *regs = drv_data->regs; - void *tx = drv_data->tx; - void *tx_end = drv_data->tx_end; - u8 n_bytes = drv_data->n_bytes; - u32 remaining_writes; - u32 fifo_avail_space; - u32 n; - u16 d; - - /* Compute how many fifo writes to do */ - remaining_writes = (u32)(tx_end - tx) / n_bytes; - fifo_avail_space = SPI_FIFO_DEPTH - - (readl(regs + SPI_TEST) & SPI_TEST_TXCNT); - if (drv_data->rx && (fifo_avail_space > SPI_FIFO_OVERFLOW_MARGIN)) - /* Fix misunderstood receive overflow */ - fifo_avail_space -= SPI_FIFO_OVERFLOW_MARGIN; - n = min(remaining_writes, fifo_avail_space); - - dev_dbg(&drv_data->pdev->dev, - "write type %s\n" - " remaining writes = %d\n" - " fifo avail space = %d\n" - " fifo writes = %d\n", - (n_bytes == 1) ? "u8" : "u16", - remaining_writes, - fifo_avail_space, - n); - - if (n > 0) { - /* Fill SPI TXFIFO */ - if (drv_data->rd_only) { - tx += n * n_bytes; - while (n--) - writel(SPI_DUMMY_u16, regs + SPI_TXDATA); - } else { - if (n_bytes == 1) { - while (n--) { - d = *(u8*)tx; - writel(d, regs + SPI_TXDATA); - tx += 1; - } - } else { - while (n--) { - d = *(u16*)tx; - writel(d, regs + SPI_TXDATA); - tx += 2; - } - } - } - - /* Trigger transfer */ - writel(readl(regs + SPI_CONTROL) | SPI_CONTROL_XCH, - regs + SPI_CONTROL); - - /* Update tx pointer */ - drv_data->tx = tx; - } - - return (tx >= tx_end); -} - -static int read(struct driver_data *drv_data) -{ - void __iomem *regs = drv_data->regs; - void *rx = drv_data->rx; - void *rx_end = drv_data->rx_end; - u8 n_bytes = drv_data->n_bytes; - u32 remaining_reads; - u32 fifo_rxcnt; - u32 n; - u16 d; - - /* Compute how many fifo reads to do */ - remaining_reads = (u32)(rx_end - rx) / n_bytes; - fifo_rxcnt = (readl(regs + SPI_TEST) & SPI_TEST_RXCNT) >> - SPI_TEST_RXCNT_LSB; - n = min(remaining_reads, fifo_rxcnt); - - dev_dbg(&drv_data->pdev->dev, - "read type %s\n" - " remaining reads = %d\n" - " fifo rx count = %d\n" - " fifo reads = %d\n", - (n_bytes == 1) ? "u8" : "u16", - remaining_reads, - fifo_rxcnt, - n); - - if (n > 0) { - /* Read SPI RXFIFO */ - if (n_bytes == 1) { - while (n--) { - d = readl(regs + SPI_RXDATA); - *((u8*)rx) = d; - rx += 1; - } - } else { - while (n--) { - d = readl(regs + SPI_RXDATA); - *((u16*)rx) = d; - rx += 2; - } - } - - /* Update rx pointer */ - drv_data->rx = rx; - } - - return (rx >= rx_end); -} - -static void *next_transfer(struct driver_data *drv_data) -{ - struct spi_message *msg = drv_data->cur_msg; - struct spi_transfer *trans = drv_data->cur_transfer; - - /* Move to next transfer */ - if (trans->transfer_list.next != &msg->transfers) { - drv_data->cur_transfer = - list_entry(trans->transfer_list.next, - struct spi_transfer, - transfer_list); - return RUNNING_STATE; - } - - return DONE_STATE; -} - -static int map_dma_buffers(struct driver_data *drv_data) -{ - struct spi_message *msg; - struct device *dev; - void *buf; - - drv_data->rx_dma_needs_unmap = 0; - drv_data->tx_dma_needs_unmap = 0; - - if (!drv_data->master_info->enable_dma || - !drv_data->cur_chip->enable_dma) - return -1; - - msg = drv_data->cur_msg; - dev = &msg->spi->dev; - if (msg->is_dma_mapped) { - if (drv_data->tx_dma) - /* The caller provided at least dma and cpu virtual - address for write; pump_transfers() will consider the - transfer as write only if cpu rx virtual address is - NULL */ - return 0; - - if (drv_data->rx_dma) { - /* The caller provided dma and cpu virtual address to - performe read only transfer --> - use drv_data->dummy_dma_buf for dummy writes to - achive reads */ - buf = &drv_data->dummy_dma_buf; - drv_data->tx_map_len = sizeof(drv_data->dummy_dma_buf); - drv_data->tx_dma = dma_map_single(dev, - buf, - drv_data->tx_map_len, - DMA_TO_DEVICE); - if (dma_mapping_error(dev, drv_data->tx_dma)) - return -1; - - drv_data->tx_dma_needs_unmap = 1; - - /* Flags transfer as rd_only for pump_transfers() DMA - regs programming (should be redundant) */ - drv_data->tx = NULL; - - return 0; - } - } - - if (!IS_DMA_ALIGNED(drv_data->rx) || !IS_DMA_ALIGNED(drv_data->tx)) - return -1; - - if (drv_data->tx == NULL) { - /* Read only message --> use drv_data->dummy_dma_buf for dummy - writes to achive reads */ - buf = &drv_data->dummy_dma_buf; - drv_data->tx_map_len = sizeof(drv_data->dummy_dma_buf); - } else { - buf = drv_data->tx; - drv_data->tx_map_len = drv_data->len; - } - drv_data->tx_dma = dma_map_single(dev, - buf, - drv_data->tx_map_len, - DMA_TO_DEVICE); - if (dma_mapping_error(dev, drv_data->tx_dma)) - return -1; - drv_data->tx_dma_needs_unmap = 1; - - /* NULL rx means write-only transfer and no map needed - * since rx DMA will not be used */ - if (drv_data->rx) { - buf = drv_data->rx; - drv_data->rx_dma = dma_map_single(dev, - buf, - drv_data->len, - DMA_FROM_DEVICE); - if (dma_mapping_error(dev, drv_data->rx_dma)) { - if (drv_data->tx_dma) { - dma_unmap_single(dev, - drv_data->tx_dma, - drv_data->tx_map_len, - DMA_TO_DEVICE); - drv_data->tx_dma_needs_unmap = 0; - } - return -1; - } - drv_data->rx_dma_needs_unmap = 1; - } - - return 0; -} - -static void unmap_dma_buffers(struct driver_data *drv_data) -{ - struct spi_message *msg = drv_data->cur_msg; - struct device *dev = &msg->spi->dev; - - if (drv_data->rx_dma_needs_unmap) { - dma_unmap_single(dev, - drv_data->rx_dma, - drv_data->len, - DMA_FROM_DEVICE); - drv_data->rx_dma_needs_unmap = 0; - } - if (drv_data->tx_dma_needs_unmap) { - dma_unmap_single(dev, - drv_data->tx_dma, - drv_data->tx_map_len, - DMA_TO_DEVICE); - drv_data->tx_dma_needs_unmap = 0; - } -} - -/* Caller already set message->status (dma is already blocked) */ -static void giveback(struct spi_message *message, struct driver_data *drv_data) -{ - void __iomem *regs = drv_data->regs; - - /* Bring SPI to sleep; restore_state() and pump_transfer() - will do new setup */ - writel(0, regs + SPI_INT_STATUS); - writel(0, regs + SPI_DMA); - - /* Unconditioned deselct */ - drv_data->cs_control(SPI_CS_DEASSERT); - - message->state = NULL; - if (message->complete) - message->complete(message->context); - - drv_data->cur_msg = NULL; - drv_data->cur_transfer = NULL; - drv_data->cur_chip = NULL; - queue_work(drv_data->workqueue, &drv_data->work); -} - -static void dma_err_handler(int channel, void *data, int errcode) -{ - struct driver_data *drv_data = data; - struct spi_message *msg = drv_data->cur_msg; - - dev_dbg(&drv_data->pdev->dev, "dma_err_handler\n"); - - /* Disable both rx and tx dma channels */ - imx_dma_disable(drv_data->rx_channel); - imx_dma_disable(drv_data->tx_channel); - unmap_dma_buffers(drv_data); - - flush(drv_data); - - msg->state = ERROR_STATE; - tasklet_schedule(&drv_data->pump_transfers); -} - -static void dma_tx_handler(int channel, void *data) -{ - struct driver_data *drv_data = data; - - dev_dbg(&drv_data->pdev->dev, "dma_tx_handler\n"); - - imx_dma_disable(channel); - - /* Now waits for TX FIFO empty */ - writel(SPI_INTEN_TE, drv_data->regs + SPI_INT_STATUS); -} - -static irqreturn_t dma_transfer(struct driver_data *drv_data) -{ - u32 status; - struct spi_message *msg = drv_data->cur_msg; - void __iomem *regs = drv_data->regs; - - status = readl(regs + SPI_INT_STATUS); - - if ((status & (SPI_INTEN_RO | SPI_STATUS_RO)) - == (SPI_INTEN_RO | SPI_STATUS_RO)) { - writel(status & ~SPI_INTEN, regs + SPI_INT_STATUS); - - imx_dma_disable(drv_data->tx_channel); - imx_dma_disable(drv_data->rx_channel); - unmap_dma_buffers(drv_data); - - flush(drv_data); - - dev_warn(&drv_data->pdev->dev, - "dma_transfer - fifo overun\n"); - - msg->state = ERROR_STATE; - tasklet_schedule(&drv_data->pump_transfers); - - return IRQ_HANDLED; - } - - if (status & SPI_STATUS_TE) { - writel(status & ~SPI_INTEN_TE, regs + SPI_INT_STATUS); - - if (drv_data->rx) { - /* Wait end of transfer before read trailing data */ - while (readl(regs + SPI_CONTROL) & SPI_CONTROL_XCH) - cpu_relax(); - - imx_dma_disable(drv_data->rx_channel); - unmap_dma_buffers(drv_data); - - /* Release chip select if requested, transfer delays are - handled in pump_transfers() */ - if (drv_data->cs_change) - drv_data->cs_control(SPI_CS_DEASSERT); - - /* Calculate number of trailing data and read them */ - dev_dbg(&drv_data->pdev->dev, - "dma_transfer - test = 0x%08X\n", - readl(regs + SPI_TEST)); - drv_data->rx = drv_data->rx_end - - ((readl(regs + SPI_TEST) & - SPI_TEST_RXCNT) >> - SPI_TEST_RXCNT_LSB)*drv_data->n_bytes; - read(drv_data); - } else { - /* Write only transfer */ - unmap_dma_buffers(drv_data); - - flush(drv_data); - } - - /* End of transfer, update total byte transfered */ - msg->actual_length += drv_data->len; - - /* Move to next transfer */ - msg->state = next_transfer(drv_data); - - /* Schedule transfer tasklet */ - tasklet_schedule(&drv_data->pump_transfers); - - return IRQ_HANDLED; - } - - /* Opps problem detected */ - return IRQ_NONE; -} - -static irqreturn_t interrupt_wronly_transfer(struct driver_data *drv_data) -{ - struct spi_message *msg = drv_data->cur_msg; - void __iomem *regs = drv_data->regs; - u32 status; - irqreturn_t handled = IRQ_NONE; - - status = readl(regs + SPI_INT_STATUS); - - if (status & SPI_INTEN_TE) { - /* TXFIFO Empty Interrupt on the last transfered word */ - writel(status & ~SPI_INTEN, regs + SPI_INT_STATUS); - dev_dbg(&drv_data->pdev->dev, - "interrupt_wronly_transfer - end of tx\n"); - - flush(drv_data); - - /* Update total byte transfered */ - msg->actual_length += drv_data->len; - - /* Move to next transfer */ - msg->state = next_transfer(drv_data); - - /* Schedule transfer tasklet */ - tasklet_schedule(&drv_data->pump_transfers); - - return IRQ_HANDLED; - } else { - while (status & SPI_STATUS_TH) { - dev_dbg(&drv_data->pdev->dev, - "interrupt_wronly_transfer - status = 0x%08X\n", - status); - - /* Pump data */ - if (write(drv_data)) { - /* End of TXFIFO writes, - now wait until TXFIFO is empty */ - writel(SPI_INTEN_TE, regs + SPI_INT_STATUS); - return IRQ_HANDLED; - } - - status = readl(regs + SPI_INT_STATUS); - - /* We did something */ - handled = IRQ_HANDLED; - } - } - - return handled; -} - -static irqreturn_t interrupt_transfer(struct driver_data *drv_data) -{ - struct spi_message *msg = drv_data->cur_msg; - void __iomem *regs = drv_data->regs; - u32 status, control; - irqreturn_t handled = IRQ_NONE; - unsigned long limit; - - status = readl(regs + SPI_INT_STATUS); - - if (status & SPI_INTEN_TE) { - /* TXFIFO Empty Interrupt on the last transfered word */ - writel(status & ~SPI_INTEN, regs + SPI_INT_STATUS); - dev_dbg(&drv_data->pdev->dev, - "interrupt_transfer - end of tx\n"); - - if (msg->state == ERROR_STATE) { - /* RXFIFO overrun was detected and message aborted */ - flush(drv_data); - } else { - /* Wait for end of transaction */ - do { - control = readl(regs + SPI_CONTROL); - } while (control & SPI_CONTROL_XCH); - - /* Release chip select if requested, transfer delays are - handled in pump_transfers */ - if (drv_data->cs_change) - drv_data->cs_control(SPI_CS_DEASSERT); - - /* Read trailing bytes */ - limit = loops_per_jiffy << 1; - while ((read(drv_data) == 0) && --limit) - cpu_relax(); - - if (limit == 0) - dev_err(&drv_data->pdev->dev, - "interrupt_transfer - " - "trailing byte read failed\n"); - else - dev_dbg(&drv_data->pdev->dev, - "interrupt_transfer - end of rx\n"); - - /* Update total byte transfered */ - msg->actual_length += drv_data->len; - - /* Move to next transfer */ - msg->state = next_transfer(drv_data); - } - - /* Schedule transfer tasklet */ - tasklet_schedule(&drv_data->pump_transfers); - - return IRQ_HANDLED; - } else { - while (status & (SPI_STATUS_TH | SPI_STATUS_RO)) { - dev_dbg(&drv_data->pdev->dev, - "interrupt_transfer - status = 0x%08X\n", - status); - - if (status & SPI_STATUS_RO) { - /* RXFIFO overrun, abort message end wait - until TXFIFO is empty */ - writel(SPI_INTEN_TE, regs + SPI_INT_STATUS); - - dev_warn(&drv_data->pdev->dev, - "interrupt_transfer - fifo overun\n" - " data not yet written = %d\n" - " data not yet read = %d\n", - data_to_write(drv_data), - data_to_read(drv_data)); - - msg->state = ERROR_STATE; - - return IRQ_HANDLED; - } - - /* Pump data */ - read(drv_data); - if (write(drv_data)) { - /* End of TXFIFO writes, - now wait until TXFIFO is empty */ - writel(SPI_INTEN_TE, regs + SPI_INT_STATUS); - return IRQ_HANDLED; - } - - status = readl(regs + SPI_INT_STATUS); - - /* We did something */ - handled = IRQ_HANDLED; - } - } - - return handled; -} - -static irqreturn_t spi_int(int irq, void *dev_id) -{ - struct driver_data *drv_data = (struct driver_data *)dev_id; - - if (!drv_data->cur_msg) { - dev_err(&drv_data->pdev->dev, - "spi_int - bad message state\n"); - /* Never fail */ - return IRQ_HANDLED; - } - - return drv_data->transfer_handler(drv_data); -} - -static inline u32 spi_speed_hz(struct driver_data *drv_data, u32 data_rate) -{ - return clk_get_rate(drv_data->clk) / (4 << ((data_rate) >> 13)); -} - -static u32 spi_data_rate(struct driver_data *drv_data, u32 speed_hz) -{ - u32 div; - u32 quantized_hz = clk_get_rate(drv_data->clk) >> 2; - - for (div = SPI_PERCLK2_DIV_MIN; - div <= SPI_PERCLK2_DIV_MAX; - div++, quantized_hz >>= 1) { - if (quantized_hz <= speed_hz) - /* Max available speed LEQ required speed */ - return div << 13; - } - return SPI_CONTROL_DATARATE_BAD; -} - -static void pump_transfers(unsigned long data) -{ - struct driver_data *drv_data = (struct driver_data *)data; - struct spi_message *message; - struct spi_transfer *transfer, *previous; - struct chip_data *chip; - void __iomem *regs; - u32 tmp, control; - - dev_dbg(&drv_data->pdev->dev, "pump_transfer\n"); - - message = drv_data->cur_msg; - - /* Handle for abort */ - if (message->state == ERROR_STATE) { - message->status = -EIO; - giveback(message, drv_data); - return; - } - - /* Handle end of message */ - if (message->state == DONE_STATE) { - message->status = 0; - giveback(message, drv_data); - return; - } - - chip = drv_data->cur_chip; - - /* Delay if requested at end of transfer*/ - transfer = drv_data->cur_transfer; - if (message->state == RUNNING_STATE) { - previous = list_entry(transfer->transfer_list.prev, - struct spi_transfer, - transfer_list); - if (previous->delay_usecs) - udelay(previous->delay_usecs); - } else { - /* START_STATE */ - message->state = RUNNING_STATE; - drv_data->cs_control = chip->cs_control; - } - - transfer = drv_data->cur_transfer; - drv_data->tx = (void *)transfer->tx_buf; - drv_data->tx_end = drv_data->tx + transfer->len; - drv_data->rx = transfer->rx_buf; - drv_data->rx_end = drv_data->rx + transfer->len; - drv_data->rx_dma = transfer->rx_dma; - drv_data->tx_dma = transfer->tx_dma; - drv_data->len = transfer->len; - drv_data->cs_change = transfer->cs_change; - drv_data->rd_only = (drv_data->tx == NULL); - - regs = drv_data->regs; - control = readl(regs + SPI_CONTROL); - - /* Bits per word setup */ - tmp = transfer->bits_per_word; - if (tmp == 0) { - /* Use device setup */ - tmp = chip->bits_per_word; - drv_data->n_bytes = chip->n_bytes; - } else - /* Use per-transfer setup */ - drv_data->n_bytes = (tmp <= 8) ? 1 : 2; - u32_EDIT(control, SPI_CONTROL_BITCOUNT_MASK, tmp - 1); - - /* Speed setup (surely valid because already checked) */ - tmp = transfer->speed_hz; - if (tmp == 0) - tmp = chip->max_speed_hz; - tmp = spi_data_rate(drv_data, tmp); - u32_EDIT(control, SPI_CONTROL_DATARATE, tmp); - - writel(control, regs + SPI_CONTROL); - - /* Assert device chip-select */ - drv_data->cs_control(SPI_CS_ASSERT); - - /* DMA cannot read/write SPI FIFOs other than 16 bits at a time; hence - if bits_per_word is less or equal 8 PIO transfers are performed. - Moreover DMA is convinient for transfer length bigger than FIFOs - byte size. */ - if ((drv_data->n_bytes == 2) && - (drv_data->len > SPI_FIFO_DEPTH*SPI_FIFO_BYTE_WIDTH) && - (map_dma_buffers(drv_data) == 0)) { - dev_dbg(&drv_data->pdev->dev, - "pump dma transfer\n" - " tx = %p\n" - " tx_dma = %08X\n" - " rx = %p\n" - " rx_dma = %08X\n" - " len = %d\n", - drv_data->tx, - (unsigned int)drv_data->tx_dma, - drv_data->rx, - (unsigned int)drv_data->rx_dma, - drv_data->len); - - /* Ensure we have the correct interrupt handler */ - drv_data->transfer_handler = dma_transfer; - - /* Trigger transfer */ - writel(readl(regs + SPI_CONTROL) | SPI_CONTROL_XCH, - regs + SPI_CONTROL); - - /* Setup tx DMA */ - if (drv_data->tx) - /* Linear source address */ - CCR(drv_data->tx_channel) = - CCR_DMOD_FIFO | - CCR_SMOD_LINEAR | - CCR_SSIZ_32 | CCR_DSIZ_16 | - CCR_REN; - else - /* Read only transfer -> fixed source address for - dummy write to achive read */ - CCR(drv_data->tx_channel) = - CCR_DMOD_FIFO | - CCR_SMOD_FIFO | - CCR_SSIZ_32 | CCR_DSIZ_16 | - CCR_REN; - - imx_dma_setup_single( - drv_data->tx_channel, - drv_data->tx_dma, - drv_data->len, - drv_data->rd_data_phys + 4, - DMA_MODE_WRITE); - - if (drv_data->rx) { - /* Setup rx DMA for linear destination address */ - CCR(drv_data->rx_channel) = - CCR_DMOD_LINEAR | - CCR_SMOD_FIFO | - CCR_DSIZ_32 | CCR_SSIZ_16 | - CCR_REN; - imx_dma_setup_single( - drv_data->rx_channel, - drv_data->rx_dma, - drv_data->len, - drv_data->rd_data_phys, - DMA_MODE_READ); - imx_dma_enable(drv_data->rx_channel); - - /* Enable SPI interrupt */ - writel(SPI_INTEN_RO, regs + SPI_INT_STATUS); - - /* Set SPI to request DMA service on both - Rx and Tx half fifo watermark */ - writel(SPI_DMA_RHDEN | SPI_DMA_THDEN, regs + SPI_DMA); - } else - /* Write only access -> set SPI to request DMA - service on Tx half fifo watermark */ - writel(SPI_DMA_THDEN, regs + SPI_DMA); - - imx_dma_enable(drv_data->tx_channel); - } else { - dev_dbg(&drv_data->pdev->dev, - "pump pio transfer\n" - " tx = %p\n" - " rx = %p\n" - " len = %d\n", - drv_data->tx, - drv_data->rx, - drv_data->len); - - /* Ensure we have the correct interrupt handler */ - if (drv_data->rx) - drv_data->transfer_handler = interrupt_transfer; - else - drv_data->transfer_handler = interrupt_wronly_transfer; - - /* Enable SPI interrupt */ - if (drv_data->rx) - writel(SPI_INTEN_TH | SPI_INTEN_RO, - regs + SPI_INT_STATUS); - else - writel(SPI_INTEN_TH, regs + SPI_INT_STATUS); - } -} - -static void pump_messages(struct work_struct *work) -{ - struct driver_data *drv_data = - container_of(work, struct driver_data, work); - unsigned long flags; - - /* Lock queue and check for queue work */ - spin_lock_irqsave(&drv_data->lock, flags); - if (list_empty(&drv_data->queue) || drv_data->run == QUEUE_STOPPED) { - drv_data->busy = 0; - spin_unlock_irqrestore(&drv_data->lock, flags); - return; - } - - /* Make sure we are not already running a message */ - if (drv_data->cur_msg) { - spin_unlock_irqrestore(&drv_data->lock, flags); - return; - } - - /* Extract head of queue */ - drv_data->cur_msg = list_entry(drv_data->queue.next, - struct spi_message, queue); - list_del_init(&drv_data->cur_msg->queue); - drv_data->busy = 1; - spin_unlock_irqrestore(&drv_data->lock, flags); - - /* Initial message state */ - drv_data->cur_msg->state = START_STATE; - drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next, - struct spi_transfer, - transfer_list); - - /* Setup the SPI using the per chip configuration */ - drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi); - restore_state(drv_data); - - /* Mark as busy and launch transfers */ - tasklet_schedule(&drv_data->pump_transfers); -} - -static int transfer(struct spi_device *spi, struct spi_message *msg) -{ - struct driver_data *drv_data = spi_master_get_devdata(spi->master); - u32 min_speed_hz, max_speed_hz, tmp; - struct spi_transfer *trans; - unsigned long flags; - - msg->actual_length = 0; - - /* Per transfer setup check */ - min_speed_hz = spi_speed_hz(drv_data, SPI_CONTROL_DATARATE_MIN); - max_speed_hz = spi->max_speed_hz; - list_for_each_entry(trans, &msg->transfers, transfer_list) { - tmp = trans->bits_per_word; - if (tmp > 16) { - dev_err(&drv_data->pdev->dev, - "message rejected : " - "invalid transfer bits_per_word (%d bits)\n", - tmp); - goto msg_rejected; - } - tmp = trans->speed_hz; - if (tmp) { - if (tmp < min_speed_hz) { - dev_err(&drv_data->pdev->dev, - "message rejected : " - "device min speed (%d Hz) exceeds " - "required transfer speed (%d Hz)\n", - min_speed_hz, - tmp); - goto msg_rejected; - } else if (tmp > max_speed_hz) { - dev_err(&drv_data->pdev->dev, - "message rejected : " - "transfer speed (%d Hz) exceeds " - "device max speed (%d Hz)\n", - tmp, - max_speed_hz); - goto msg_rejected; - } - } - } - - /* Message accepted */ - msg->status = -EINPROGRESS; - msg->state = START_STATE; - - spin_lock_irqsave(&drv_data->lock, flags); - if (drv_data->run == QUEUE_STOPPED) { - spin_unlock_irqrestore(&drv_data->lock, flags); - return -ESHUTDOWN; - } - - list_add_tail(&msg->queue, &drv_data->queue); - if (drv_data->run == QUEUE_RUNNING && !drv_data->busy) - queue_work(drv_data->workqueue, &drv_data->work); - - spin_unlock_irqrestore(&drv_data->lock, flags); - return 0; - -msg_rejected: - /* Message rejected and not queued */ - msg->status = -EINVAL; - msg->state = ERROR_STATE; - if (msg->complete) - msg->complete(msg->context); - return -EINVAL; -} - -/* On first setup bad values must free chip_data memory since will cause - spi_new_device to fail. Bad value setup from protocol driver are simply not - applied and notified to the calling driver. */ -static int setup(struct spi_device *spi) -{ - struct driver_data *drv_data = spi_master_get_devdata(spi->master); - struct spi_imx_chip *chip_info; - struct chip_data *chip; - int first_setup = 0; - u32 tmp; - int status = 0; - - /* Get controller data */ - chip_info = spi->controller_data; - - /* Get controller_state */ - chip = spi_get_ctldata(spi); - if (chip == NULL) { - first_setup = 1; - - chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); - if (!chip) { - dev_err(&spi->dev, - "setup - cannot allocate controller state\n"); - return -ENOMEM; - } - chip->control = SPI_DEFAULT_CONTROL; - - if (chip_info == NULL) { - /* spi_board_info.controller_data not is supplied */ - chip_info = kzalloc(sizeof(struct spi_imx_chip), - GFP_KERNEL); - if (!chip_info) { - dev_err(&spi->dev, - "setup - " - "cannot allocate controller data\n"); - status = -ENOMEM; - goto err_first_setup; - } - /* Set controller data default value */ - chip_info->enable_loopback = - SPI_DEFAULT_ENABLE_LOOPBACK; - chip_info->enable_dma = SPI_DEFAULT_ENABLE_DMA; - chip_info->ins_ss_pulse = 1; - chip_info->bclk_wait = SPI_DEFAULT_PERIOD_WAIT; - chip_info->cs_control = null_cs_control; - } - } - - /* Now set controller state based on controller data */ - - if (first_setup) { - /* SPI loopback */ - if (chip_info->enable_loopback) - chip->test = SPI_TEST_LBC; - else - chip->test = 0; - - /* SPI dma driven */ - chip->enable_dma = chip_info->enable_dma; - - /* SPI /SS pulse between spi burst */ - if (chip_info->ins_ss_pulse) - u32_EDIT(chip->control, - SPI_CONTROL_SSCTL, SPI_CONTROL_SSCTL_1); - else - u32_EDIT(chip->control, - SPI_CONTROL_SSCTL, SPI_CONTROL_SSCTL_0); - - /* SPI bclk waits between each bits_per_word spi burst */ - if (chip_info->bclk_wait > SPI_PERIOD_MAX_WAIT) { - dev_err(&spi->dev, - "setup - " - "bclk_wait exceeds max allowed (%d)\n", - SPI_PERIOD_MAX_WAIT); - goto err_first_setup; - } - chip->period = SPI_PERIOD_CSRC_BCLK | - (chip_info->bclk_wait & SPI_PERIOD_WAIT); - } - - /* SPI mode */ - tmp = spi->mode; - if (tmp & SPI_CS_HIGH) { - u32_EDIT(chip->control, - SPI_CONTROL_SSPOL, SPI_CONTROL_SSPOL_ACT_HIGH); - } - switch (tmp & SPI_MODE_3) { - case SPI_MODE_0: - tmp = 0; - break; - case SPI_MODE_1: - tmp = SPI_CONTROL_PHA_1; - break; - case SPI_MODE_2: - tmp = SPI_CONTROL_POL_ACT_LOW; - break; - default: - /* SPI_MODE_3 */ - tmp = SPI_CONTROL_PHA_1 | SPI_CONTROL_POL_ACT_LOW; - break; - } - u32_EDIT(chip->control, SPI_CONTROL_POL | SPI_CONTROL_PHA, tmp); - - /* SPI word width */ - tmp = spi->bits_per_word; - if (tmp > 16) { - status = -EINVAL; - dev_err(&spi->dev, - "setup - " - "invalid bits_per_word (%d)\n", - tmp); - if (first_setup) - goto err_first_setup; - else { - /* Undo setup using chip as backup copy */ - tmp = chip->bits_per_word; - spi->bits_per_word = tmp; - } - } - chip->bits_per_word = tmp; - u32_EDIT(chip->control, SPI_CONTROL_BITCOUNT_MASK, tmp - 1); - chip->n_bytes = (tmp <= 8) ? 1 : 2; - - /* SPI datarate */ - tmp = spi_data_rate(drv_data, spi->max_speed_hz); - if (tmp == SPI_CONTROL_DATARATE_BAD) { - status = -EINVAL; - dev_err(&spi->dev, - "setup - " - "HW min speed (%d Hz) exceeds required " - "max speed (%d Hz)\n", - spi_speed_hz(drv_data, SPI_CONTROL_DATARATE_MIN), - spi->max_speed_hz); - if (first_setup) - goto err_first_setup; - else - /* Undo setup using chip as backup copy */ - spi->max_speed_hz = chip->max_speed_hz; - } else { - u32_EDIT(chip->control, SPI_CONTROL_DATARATE, tmp); - /* Actual rounded max_speed_hz */ - tmp = spi_speed_hz(drv_data, tmp); - spi->max_speed_hz = tmp; - chip->max_speed_hz = tmp; - } - - /* SPI chip-select management */ - if (chip_info->cs_control) - chip->cs_control = chip_info->cs_control; - else - chip->cs_control = null_cs_control; - - /* Save controller_state */ - spi_set_ctldata(spi, chip); - - /* Summary */ - dev_dbg(&spi->dev, - "setup succeded\n" - " loopback enable = %s\n" - " dma enable = %s\n" - " insert /ss pulse = %s\n" - " period wait = %d\n" - " mode = %d\n" - " bits per word = %d\n" - " min speed = %d Hz\n" - " rounded max speed = %d Hz\n", - chip->test & SPI_TEST_LBC ? "Yes" : "No", - chip->enable_dma ? "Yes" : "No", - chip->control & SPI_CONTROL_SSCTL ? "Yes" : "No", - chip->period & SPI_PERIOD_WAIT, - spi->mode, - spi->bits_per_word, - spi_speed_hz(drv_data, SPI_CONTROL_DATARATE_MIN), - spi->max_speed_hz); - return status; - -err_first_setup: - kfree(chip); - return status; -} - -static void cleanup(struct spi_device *spi) -{ - kfree(spi_get_ctldata(spi)); -} - -static int __init init_queue(struct driver_data *drv_data) -{ - INIT_LIST_HEAD(&drv_data->queue); - spin_lock_init(&drv_data->lock); - - drv_data->run = QUEUE_STOPPED; - drv_data->busy = 0; - - tasklet_init(&drv_data->pump_transfers, - pump_transfers, (unsigned long)drv_data); - - INIT_WORK(&drv_data->work, pump_messages); - drv_data->workqueue = create_singlethread_workqueue( - dev_name(drv_data->master->dev.parent)); - if (drv_data->workqueue == NULL) - return -EBUSY; - - return 0; -} - -static int start_queue(struct driver_data *drv_data) -{ - unsigned long flags; - - spin_lock_irqsave(&drv_data->lock, flags); - - if (drv_data->run == QUEUE_RUNNING || drv_data->busy) { - spin_unlock_irqrestore(&drv_data->lock, flags); - return -EBUSY; - } - - drv_data->run = QUEUE_RUNNING; - drv_data->cur_msg = NULL; - drv_data->cur_transfer = NULL; - drv_data->cur_chip = NULL; - spin_unlock_irqrestore(&drv_data->lock, flags); - - queue_work(drv_data->workqueue, &drv_data->work); - - return 0; -} - -static int stop_queue(struct driver_data *drv_data) -{ - unsigned long flags; - unsigned limit = 500; - int status = 0; - - spin_lock_irqsave(&drv_data->lock, flags); - - /* This is a bit lame, but is optimized for the common execution path. - * A wait_queue on the drv_data->busy could be used, but then the common - * execution path (pump_messages) would be required to call wake_up or - * friends on every SPI message. Do this instead */ - drv_data->run = QUEUE_STOPPED; - while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) { - spin_unlock_irqrestore(&drv_data->lock, flags); - msleep(10); - spin_lock_irqsave(&drv_data->lock, flags); - } - - if (!list_empty(&drv_data->queue) || drv_data->busy) - status = -EBUSY; - - spin_unlock_irqrestore(&drv_data->lock, flags); - - return status; -} - -static int destroy_queue(struct driver_data *drv_data) -{ - int status; - - status = stop_queue(drv_data); - if (status != 0) - return status; - - if (drv_data->workqueue) - destroy_workqueue(drv_data->workqueue); - - return 0; -} - -static int __init spi_imx_probe(struct platform_device *pdev) -{ - struct device *dev = &pdev->dev; - struct spi_imx_master *platform_info; - struct spi_master *master; - struct driver_data *drv_data; - struct resource *res; - int irq, status = 0; - - platform_info = dev->platform_data; - if (platform_info == NULL) { - dev_err(&pdev->dev, "probe - no platform data supplied\n"); - status = -ENODEV; - goto err_no_pdata; - } - - /* Allocate master with space for drv_data */ - master = spi_alloc_master(dev, sizeof(struct driver_data)); - if (!master) { - dev_err(&pdev->dev, "probe - cannot alloc spi_master\n"); - status = -ENOMEM; - goto err_no_mem; - } - drv_data = spi_master_get_devdata(master); - drv_data->master = master; - drv_data->master_info = platform_info; - drv_data->pdev = pdev; - - /* the spi->mode bits understood by this driver: */ - master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; - - master->bus_num = pdev->id; - master->num_chipselect = platform_info->num_chipselect; - master->dma_alignment = DMA_ALIGNMENT; - master->cleanup = cleanup; - master->setup = setup; - master->transfer = transfer; - - drv_data->dummy_dma_buf = SPI_DUMMY_u32; - - drv_data->clk = clk_get(&pdev->dev, "perclk2"); - if (IS_ERR(drv_data->clk)) { - dev_err(&pdev->dev, "probe - cannot get clock\n"); - status = PTR_ERR(drv_data->clk); - goto err_no_clk; - } - clk_enable(drv_data->clk); - - /* Find and map resources */ - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) { - dev_err(&pdev->dev, "probe - MEM resources not defined\n"); - status = -ENODEV; - goto err_no_iores; - } - drv_data->ioarea = request_mem_region(res->start, - res->end - res->start + 1, - pdev->name); - if (drv_data->ioarea == NULL) { - dev_err(&pdev->dev, "probe - cannot reserve region\n"); - status = -ENXIO; - goto err_no_iores; - } - drv_data->regs = ioremap(res->start, res->end - res->start + 1); - if (drv_data->regs == NULL) { - dev_err(&pdev->dev, "probe - cannot map IO\n"); - status = -ENXIO; - goto err_no_iomap; - } - drv_data->rd_data_phys = (dma_addr_t)res->start; - - /* Attach to IRQ */ - irq = platform_get_irq(pdev, 0); - if (irq < 0) { - dev_err(&pdev->dev, "probe - IRQ resource not defined\n"); - status = -ENODEV; - goto err_no_irqres; - } - status = request_irq(irq, spi_int, IRQF_DISABLED, - dev_name(dev), drv_data); - if (status < 0) { - dev_err(&pdev->dev, "probe - cannot get IRQ (%d)\n", status); - goto err_no_irqres; - } - - /* Setup DMA if requested */ - drv_data->tx_channel = -1; - drv_data->rx_channel = -1; - if (platform_info->enable_dma) { - /* Get rx DMA channel */ - drv_data->rx_channel = imx_dma_request_by_prio("spi_imx_rx", - DMA_PRIO_HIGH); - if (drv_data->rx_channel < 0) { - dev_err(dev, - "probe - problem (%d) requesting rx channel\n", - drv_data->rx_channel); - goto err_no_rxdma; - } else - imx_dma_setup_handlers(drv_data->rx_channel, NULL, - dma_err_handler, drv_data); - - /* Get tx DMA channel */ - drv_data->tx_channel = imx_dma_request_by_prio("spi_imx_tx", - DMA_PRIO_MEDIUM); - if (drv_data->tx_channel < 0) { - dev_err(dev, - "probe - problem (%d) requesting tx channel\n", - drv_data->tx_channel); - imx_dma_free(drv_data->rx_channel); - goto err_no_txdma; - } else - imx_dma_setup_handlers(drv_data->tx_channel, - dma_tx_handler, dma_err_handler, - drv_data); - - /* Set request source and burst length for allocated channels */ - switch (drv_data->pdev->id) { - case 1: - /* Using SPI1 */ - RSSR(drv_data->rx_channel) = DMA_REQ_SPI1_R; - RSSR(drv_data->tx_channel) = DMA_REQ_SPI1_T; - break; - case 2: - /* Using SPI2 */ - RSSR(drv_data->rx_channel) = DMA_REQ_SPI2_R; - RSSR(drv_data->tx_channel) = DMA_REQ_SPI2_T; - break; - default: - dev_err(dev, "probe - bad SPI Id\n"); - imx_dma_free(drv_data->rx_channel); - imx_dma_free(drv_data->tx_channel); - status = -ENODEV; - goto err_no_devid; - } - BLR(drv_data->rx_channel) = SPI_DMA_BLR; - BLR(drv_data->tx_channel) = SPI_DMA_BLR; - } - - /* Load default SPI configuration */ - writel(SPI_RESET_START, drv_data->regs + SPI_RESET); - writel(0, drv_data->regs + SPI_RESET); - writel(SPI_DEFAULT_CONTROL, drv_data->regs + SPI_CONTROL); - - /* Initial and start queue */ - status = init_queue(drv_data); - if (status != 0) { - dev_err(&pdev->dev, "probe - problem initializing queue\n"); - goto err_init_queue; - } - status = start_queue(drv_data); - if (status != 0) { - dev_err(&pdev->dev, "probe - problem starting queue\n"); - goto err_start_queue; - } - - /* Register with the SPI framework */ - platform_set_drvdata(pdev, drv_data); - status = spi_register_master(master); - if (status != 0) { - dev_err(&pdev->dev, "probe - problem registering spi master\n"); - goto err_spi_register; - } - - dev_dbg(dev, "probe succeded\n"); - return 0; - -err_init_queue: -err_start_queue: -err_spi_register: - destroy_queue(drv_data); - -err_no_rxdma: -err_no_txdma: -err_no_devid: - free_irq(irq, drv_data); - -err_no_irqres: - iounmap(drv_data->regs); - -err_no_iomap: - release_resource(drv_data->ioarea); - kfree(drv_data->ioarea); - -err_no_iores: - clk_disable(drv_data->clk); - clk_put(drv_data->clk); - -err_no_clk: - spi_master_put(master); - -err_no_pdata: -err_no_mem: - return status; -} - -static int __exit spi_imx_remove(struct platform_device *pdev) -{ - struct driver_data *drv_data = platform_get_drvdata(pdev); - int irq; - int status = 0; - - if (!drv_data) - return 0; - - tasklet_kill(&drv_data->pump_transfers); - - /* Remove the queue */ - status = destroy_queue(drv_data); - if (status != 0) { - dev_err(&pdev->dev, "queue remove failed (%d)\n", status); - return status; - } - - /* Reset SPI */ - writel(SPI_RESET_START, drv_data->regs + SPI_RESET); - writel(0, drv_data->regs + SPI_RESET); - - /* Release DMA */ - if (drv_data->master_info->enable_dma) { - RSSR(drv_data->rx_channel) = 0; - RSSR(drv_data->tx_channel) = 0; - imx_dma_free(drv_data->tx_channel); - imx_dma_free(drv_data->rx_channel); - } - - /* Release IRQ */ - irq = platform_get_irq(pdev, 0); - if (irq >= 0) - free_irq(irq, drv_data); - - clk_disable(drv_data->clk); - clk_put(drv_data->clk); - - /* Release map resources */ - iounmap(drv_data->regs); - release_resource(drv_data->ioarea); - kfree(drv_data->ioarea); - - /* Disconnect from the SPI framework */ - spi_unregister_master(drv_data->master); - spi_master_put(drv_data->master); - - /* Prevent double remove */ - platform_set_drvdata(pdev, NULL); - - dev_dbg(&pdev->dev, "remove succeded\n"); - - return 0; -} - -static void spi_imx_shutdown(struct platform_device *pdev) -{ - struct driver_data *drv_data = platform_get_drvdata(pdev); - - /* Reset SPI */ - writel(SPI_RESET_START, drv_data->regs + SPI_RESET); - writel(0, drv_data->regs + SPI_RESET); - - dev_dbg(&pdev->dev, "shutdown succeded\n"); -} - -#ifdef CONFIG_PM - -static int spi_imx_suspend(struct platform_device *pdev, pm_message_t state) -{ - struct driver_data *drv_data = platform_get_drvdata(pdev); - int status = 0; - - status = stop_queue(drv_data); - if (status != 0) { - dev_warn(&pdev->dev, "suspend cannot stop queue\n"); - return status; - } - - dev_dbg(&pdev->dev, "suspended\n"); - - return 0; -} - -static int spi_imx_resume(struct platform_device *pdev) -{ - struct driver_data *drv_data = platform_get_drvdata(pdev); - int status = 0; - - /* Start the queue running */ - status = start_queue(drv_data); - if (status != 0) - dev_err(&pdev->dev, "problem starting queue (%d)\n", status); - else - dev_dbg(&pdev->dev, "resumed\n"); - - return status; -} -#else -#define spi_imx_suspend NULL -#define spi_imx_resume NULL -#endif /* CONFIG_PM */ - -/* work with hotplug and coldplug */ -MODULE_ALIAS("platform:spi_imx"); - -static struct platform_driver driver = { - .driver = { - .name = "spi_imx", - .owner = THIS_MODULE, - }, - .remove = __exit_p(spi_imx_remove), - .shutdown = spi_imx_shutdown, - .suspend = spi_imx_suspend, - .resume = spi_imx_resume, -}; - -static int __init spi_imx_init(void) -{ - return platform_driver_probe(&driver, spi_imx_probe); -} -module_init(spi_imx_init); - -static void __exit spi_imx_exit(void) -{ - platform_driver_unregister(&driver); -} -module_exit(spi_imx_exit); - -MODULE_AUTHOR("Andrea Paterniani, <a.paterniani@swapp-eng.it>"); -MODULE_DESCRIPTION("iMX SPI Controller Driver"); -MODULE_LICENSE("GPL"); |