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path: root/target/linux/ramips/files-3.7/drivers/spi/spi-ramips.c
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Diffstat (limited to 'target/linux/ramips/files-3.7/drivers/spi/spi-ramips.c')
-rw-r--r--target/linux/ramips/files-3.7/drivers/spi/spi-ramips.c559
1 files changed, 0 insertions, 559 deletions
diff --git a/target/linux/ramips/files-3.7/drivers/spi/spi-ramips.c b/target/linux/ramips/files-3.7/drivers/spi/spi-ramips.c
deleted file mode 100644
index d2ceaf3b8d..0000000000
--- a/target/linux/ramips/files-3.7/drivers/spi/spi-ramips.c
+++ /dev/null
@@ -1,559 +0,0 @@
-/*
- * ramips_spi.c -- Ralink RT288x/RT305x SPI controller driver
- *
- * Copyright (C) 2011 Sergiy <piratfm@gmail.com>
- * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
- *
- * 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/module.h>
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/delay.h>
-#include <linux/platform_device.h>
-#include <linux/io.h>
-#include <linux/spi/spi.h>
-
-#define DRIVER_NAME "ramips-spi"
-#define RALINK_NUM_CHIPSELECTS 1 /* only one slave is supported*/
-#define RALINK_SPI_WAIT_RDY_MAX_LOOP 2000 /* in usec */
-
-#define RAMIPS_SPI_STAT 0x00
-#define RAMIPS_SPI_CFG 0x10
-#define RAMIPS_SPI_CTL 0x14
-#define RAMIPS_SPI_DATA 0x20
-
-/* SPISTAT register bit field */
-#define SPISTAT_BUSY BIT(0)
-
-/* SPICFG register bit field */
-#define SPICFG_LSBFIRST 0
-#define SPICFG_MSBFIRST BIT(8)
-#define SPICFG_SPICLKPOL BIT(6)
-#define SPICFG_RXCLKEDGE_FALLING BIT(5)
-#define SPICFG_TXCLKEDGE_FALLING BIT(4)
-#define SPICFG_SPICLK_PRESCALE_MASK 0x7
-#define SPICFG_SPICLK_DIV2 0
-#define SPICFG_SPICLK_DIV4 1
-#define SPICFG_SPICLK_DIV8 2
-#define SPICFG_SPICLK_DIV16 3
-#define SPICFG_SPICLK_DIV32 4
-#define SPICFG_SPICLK_DIV64 5
-#define SPICFG_SPICLK_DIV128 6
-#define SPICFG_SPICLK_DISABLE 7
-
-/* SPICTL register bit field */
-#define SPICTL_HIZSDO BIT(3)
-#define SPICTL_STARTWR BIT(2)
-#define SPICTL_STARTRD BIT(1)
-#define SPICTL_SPIENA BIT(0)
-
-#ifdef DEBUG
-#define spi_debug(args...) printk(args)
-#else
-#define spi_debug(args...)
-#endif
-
-struct ramips_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 sys_freq;
- unsigned int speed;
-
- struct clk *clk;
-};
-
-static struct workqueue_struct *ramips_spi_wq;
-
-static inline struct ramips_spi *ramips_spidev_to_rs(struct spi_device *spi)
-{
- return spi_master_get_devdata(spi->master);
-}
-
-static inline u32 ramips_spi_read(struct ramips_spi *rs, u32 reg)
-{
- return ioread32(rs->base + reg);
-}
-
-static inline void ramips_spi_write(struct ramips_spi *rs, u32 reg, u32 val)
-{
- iowrite32(val, rs->base + reg);
-}
-
-static inline void ramips_spi_setbits(struct ramips_spi *rs, u32 reg, u32 mask)
-{
- void __iomem *addr = rs->base + reg;
- u32 val;
-
- val = ioread32(addr);
- val |= mask;
- iowrite32(val, addr);
-}
-
-static inline void ramips_spi_clrbits(struct ramips_spi *rs, u32 reg, u32 mask)
-{
- void __iomem *addr = rs->base + reg;
- u32 val;
-
- val = ioread32(addr);
- val &= ~mask;
- iowrite32(val, addr);
-}
-
-static int ramips_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
-{
- struct ramips_spi *rs = ramips_spidev_to_rs(spi);
- u32 rate;
- u32 prescale;
- u32 reg;
-
- spi_debug("%s: speed:%u\n", __func__, speed);
-
- /*
- * the supported rates are: 2,4,8...128
- * round up as we look for equal or less speed
- */
- rate = DIV_ROUND_UP(rs->sys_freq, speed);
- spi_debug("%s: rate-1:%u\n", __func__, rate);
- rate = roundup_pow_of_two(rate);
- spi_debug("%s: rate-2:%u\n", __func__, rate);
-
- /* check if requested speed is too small */
- if (rate > 128)
- return -EINVAL;
-
- if (rate < 2)
- rate = 2;
-
- /* Convert the rate to SPI clock divisor value. */
- prescale = ilog2(rate/2);
- spi_debug("%s: prescale:%u\n", __func__, prescale);
-
- reg = ramips_spi_read(rs, RAMIPS_SPI_CFG);
- reg = ((reg & ~SPICFG_SPICLK_PRESCALE_MASK) | prescale);
- ramips_spi_write(rs, RAMIPS_SPI_CFG, reg);
- rs->speed = speed;
- return 0;
-}
-
-/*
- * called only when no transfer is active on the bus
- */
-static int
-ramips_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
-{
- struct ramips_spi *rs = ramips_spidev_to_rs(spi);
- unsigned int speed = spi->max_speed_hz;
- int rc;
- unsigned int bits_per_word = 8;
-
- if ((t != NULL) && t->speed_hz)
- speed = t->speed_hz;
-
- if ((t != NULL) && t->bits_per_word)
- bits_per_word = t->bits_per_word;
-
- if (rs->speed != speed) {
- spi_debug("%s: speed_hz:%u\n", __func__, speed);
- rc = ramips_spi_baudrate_set(spi, speed);
- if (rc)
- return rc;
- }
-
- if (bits_per_word != 8) {
- spi_debug("%s: bad bits_per_word: %u\n", __func__,
- bits_per_word);
- return -EINVAL;
- }
-
- return 0;
-}
-
-static void ramips_spi_set_cs(struct ramips_spi *rs, int enable)
-{
- if (enable)
- ramips_spi_clrbits(rs, RAMIPS_SPI_CTL, SPICTL_SPIENA);
- else
- ramips_spi_setbits(rs, RAMIPS_SPI_CTL, SPICTL_SPIENA);
-}
-
-static inline int ramips_spi_wait_till_ready(struct ramips_spi *rs)
-{
- int i;
-
- for (i = 0; i < RALINK_SPI_WAIT_RDY_MAX_LOOP; i++) {
- u32 status;
-
- status = ramips_spi_read(rs, RAMIPS_SPI_STAT);
- if ((status & SPISTAT_BUSY) == 0)
- return 0;
-
- udelay(1);
- }
-
- return -ETIMEDOUT;
-}
-
-static unsigned int
-ramips_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
-{
- struct ramips_spi *rs = ramips_spidev_to_rs(spi);
- unsigned count = 0;
- u8 *rx = xfer->rx_buf;
- const u8 *tx = xfer->tx_buf;
- int err;
-
- spi_debug("%s(%d): %s %s\n", __func__, xfer->len,
- (tx != NULL) ? "tx" : " ",
- (rx != NULL) ? "rx" : " ");
-
- if (tx) {
- for (count = 0; count < xfer->len; count++) {
- ramips_spi_write(rs, RAMIPS_SPI_DATA, tx[count]);
- ramips_spi_setbits(rs, RAMIPS_SPI_CTL, SPICTL_STARTWR);
- err = ramips_spi_wait_till_ready(rs);
- if (err) {
- dev_err(&spi->dev, "TX failed, err=%d\n", err);
- goto out;
- }
- }
- }
-
- if (rx) {
- for (count = 0; count < xfer->len; count++) {
- ramips_spi_setbits(rs, RAMIPS_SPI_CTL, SPICTL_STARTRD);
- err = ramips_spi_wait_till_ready(rs);
- if (err) {
- dev_err(&spi->dev, "RX failed, err=%d\n", err);
- goto out;
- }
- rx[count] = (u8) ramips_spi_read(rs, RAMIPS_SPI_DATA);
- }
- }
-
-out:
- return count;
-}
-
-static void ramips_spi_work(struct work_struct *work)
-{
- struct ramips_spi *rs =
- container_of(work, struct ramips_spi, work);
-
- spin_lock_irq(&rs->lock);
- while (!list_empty(&rs->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(rs->msg_queue.next, struct spi_message,
- queue);
-
- list_del_init(&m->queue);
- spin_unlock_irq(&rs->lock);
-
- spi = m->spi;
-
- /* Load defaults */
- status = ramips_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 = ramips_spi_setup_transfer(spi, t);
- if (status < 0)
- break;
- if (!t->speed_hz && !t->bits_per_word)
- par_override = 0;
- }
-
- if (!cs_active) {
- ramips_spi_set_cs(rs, 1);
- cs_active = 1;
- }
-
- if (t->len)
- m->actual_length +=
- ramips_spi_write_read(spi, t);
-
- if (t->delay_usecs)
- udelay(t->delay_usecs);
-
- if (t->cs_change) {
- ramips_spi_set_cs(rs, 0);
- cs_active = 0;
- }
- }
-
-msg_done:
- if (cs_active)
- ramips_spi_set_cs(rs, 0);
-
- m->status = status;
- m->complete(m->context);
-
- spin_lock_irq(&rs->lock);
- }
-
- spin_unlock_irq(&rs->lock);
-}
-
-static int ramips_spi_setup(struct spi_device *spi)
-{
- struct ramips_spi *rs = ramips_spidev_to_rs(spi);
-
- if ((spi->max_speed_hz == 0) ||
- (spi->max_speed_hz > (rs->sys_freq / 2)))
- spi->max_speed_hz = (rs->sys_freq / 2);
-
- if (spi->max_speed_hz < (rs->sys_freq/128)) {
- dev_err(&spi->dev, "setup: requested speed too low %d Hz\n",
- spi->max_speed_hz);
- return -EINVAL;
- }
-
- if (spi->bits_per_word != 0 && spi->bits_per_word != 8) {
- dev_err(&spi->dev,
- "setup: requested bits per words - os wrong %d bpw\n",
- spi->bits_per_word);
- return -EINVAL;
- }
-
- if (spi->bits_per_word == 0)
- spi->bits_per_word = 8;
-
- /*
- * baudrate & width will be set ramips_spi_setup_transfer
- */
- return 0;
-}
-
-static int ramips_spi_transfer(struct spi_device *spi, struct spi_message *m)
-{
- struct ramips_spi *rs;
- 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;
-
- rs = ramips_spidev_to_rs(spi);
-
- 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->bits_per_word)
- bits_per_word = t->bits_per_word;
-
- if (bits_per_word != 8) {
- dev_err(&spi->dev,
- "message rejected : "
- "invalid transfer bits_per_word (%d bits)\n",
- bits_per_word);
- goto msg_rejected;
- }
-
- if (t->speed_hz && t->speed_hz < (rs->sys_freq/128)) {
- dev_err(&spi->dev,
- "message rejected : "
- "device min speed (%d Hz) exceeds "
- "required transfer speed (%d Hz)\n",
- (rs->sys_freq/128), t->speed_hz);
- goto msg_rejected;
- }
- }
-
-
- spin_lock_irqsave(&rs->lock, flags);
- list_add_tail(&m->queue, &rs->msg_queue);
- queue_work(ramips_spi_wq, &rs->work);
- spin_unlock_irqrestore(&rs->lock, flags);
-
- return 0;
-msg_rejected:
- /* Message rejected and not queued */
- m->status = -EINVAL;
- if (m->complete)
- m->complete(m->context);
- return -EINVAL;
-}
-
-static void __init ramips_spi_reset(struct ramips_spi *rs)
-{
- ramips_spi_write(rs, RAMIPS_SPI_CFG,
- SPICFG_MSBFIRST | SPICFG_TXCLKEDGE_FALLING |
- SPICFG_SPICLK_DIV16 | SPICFG_SPICLKPOL);
- ramips_spi_write(rs, RAMIPS_SPI_CTL, SPICTL_HIZSDO | SPICTL_SPIENA);
-}
-
-static int __init ramips_spi_probe(struct platform_device *pdev)
-{
- struct spi_master *master;
- struct ramips_spi *rs;
- struct resource *r;
- int status = 0;
-
- master = spi_alloc_master(&pdev->dev, sizeof(*rs));
- if (master == NULL) {
- dev_dbg(&pdev->dev, "master allocation failed\n");
- return -ENOMEM;
- }
-
- if (pdev->id != -1)
- master->bus_num = pdev->id;
-
- /* we support only mode 0, and no options */
- master->mode_bits = 0;
-
- master->setup = ramips_spi_setup;
- master->transfer = ramips_spi_transfer;
- master->num_chipselect = RALINK_NUM_CHIPSELECTS;
-
- dev_set_drvdata(&pdev->dev, master);
-
- rs = spi_master_get_devdata(master);
- rs->master = master;
-
- rs->clk = clk_get(NULL, "sys");
- if (IS_ERR(rs->clk)) {
- status = PTR_ERR(rs->clk);
- dev_err(&pdev->dev, "unable to get SYS clock, err=%d\n",
- status);
- goto out_put_master;
- }
-
- status = clk_enable(rs->clk);
- if (status)
- goto out_put_clk;
-
- rs->sys_freq = clk_get_rate(rs->clk);
- spi_debug("%s: sys_freq: %ld\n", __func__, rs->sys_freq);
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (r == NULL) {
- status = -ENODEV;
- goto out_disable_clk;
- }
-
- if (!request_mem_region(r->start, (r->end - r->start) + 1,
- dev_name(&pdev->dev))) {
- status = -EBUSY;
- goto out_disable_clk;
- }
-
- rs->base = ioremap(r->start, resource_size(r));
- if (rs->base == NULL) {
- dev_err(&pdev->dev, "ioremap failed\n");
- status = -ENOMEM;
- goto out_rel_mem;
- }
-
- INIT_WORK(&rs->work, ramips_spi_work);
-
- spin_lock_init(&rs->lock);
- INIT_LIST_HEAD(&rs->msg_queue);
-
- ramips_spi_reset(rs);
-
- status = spi_register_master(master);
- if (status)
- goto out_unmap_base;
-
- return 0;
-
-out_unmap_base:
- iounmap(rs->base);
-out_rel_mem:
- release_mem_region(r->start, (r->end - r->start) + 1);
-out_disable_clk:
- clk_disable(rs->clk);
-out_put_clk:
- clk_put(rs->clk);
-out_put_master:
- spi_master_put(master);
- return status;
-}
-
-static int ramips_spi_remove(struct platform_device *pdev)
-{
- struct spi_master *master;
- struct ramips_spi *rs;
- struct resource *r;
-
- master = dev_get_drvdata(&pdev->dev);
- rs = spi_master_get_devdata(master);
-
- cancel_work_sync(&rs->work);
-
- iounmap(rs->base);
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(r->start, (r->end - r->start) + 1);
-
- clk_disable(rs->clk);
- clk_put(rs->clk);
- spi_unregister_master(master);
-
- return 0;
-}
-
-MODULE_ALIAS("platform:" DRIVER_NAME);
-
-static struct platform_driver ramips_spi_driver = {
- .driver = {
- .name = DRIVER_NAME,
- .owner = THIS_MODULE,
- },
- .remove = ramips_spi_remove,
-};
-
-static int __init ramips_spi_init(void)
-{
- ramips_spi_wq = create_singlethread_workqueue(
- ramips_spi_driver.driver.name);
- if (ramips_spi_wq == NULL)
- return -ENOMEM;
-
- return platform_driver_probe(&ramips_spi_driver, ramips_spi_probe);
-}
-module_init(ramips_spi_init);
-
-static void __exit ramips_spi_exit(void)
-{
- flush_workqueue(ramips_spi_wq);
- platform_driver_unregister(&ramips_spi_driver);
-
- destroy_workqueue(ramips_spi_wq);
-}
-module_exit(ramips_spi_exit);
-
-MODULE_DESCRIPTION("Ralink SPI driver");
-MODULE_AUTHOR("Sergiy <piratfm@gmail.com>");
-MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
-MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-05 03:34:40 +0000