diff options
Diffstat (limited to 'drivers/spi/spi-omap-100k.c')
-rw-r--r-- | drivers/spi/spi-omap-100k.c | 490 |
1 files changed, 0 insertions, 490 deletions
diff --git a/drivers/spi/spi-omap-100k.c b/drivers/spi/spi-omap-100k.c deleted file mode 100644 index 061f7394e5b9..000000000000 --- a/drivers/spi/spi-omap-100k.c +++ /dev/null @@ -1,490 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * OMAP7xx SPI 100k controller driver - * Author: Fabrice Crohas <fcrohas@gmail.com> - * from original omap1_mcspi driver - * - * Copyright (C) 2005, 2006 Nokia Corporation - * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and - * Juha Yrjola <juha.yrjola@nokia.com> - */ -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/interrupt.h> -#include <linux/module.h> -#include <linux/device.h> -#include <linux/delay.h> -#include <linux/platform_device.h> -#include <linux/pm_runtime.h> -#include <linux/err.h> -#include <linux/clk.h> -#include <linux/io.h> -#include <linux/slab.h> - -#include <linux/spi/spi.h> - -#define OMAP1_SPI100K_MAX_FREQ 48000000 - -#define ICR_SPITAS (OMAP7XX_ICR_BASE + 0x12) - -#define SPI_SETUP1 0x00 -#define SPI_SETUP2 0x02 -#define SPI_CTRL 0x04 -#define SPI_STATUS 0x06 -#define SPI_TX_LSB 0x08 -#define SPI_TX_MSB 0x0a -#define SPI_RX_LSB 0x0c -#define SPI_RX_MSB 0x0e - -#define SPI_SETUP1_INT_READ_ENABLE (1UL << 5) -#define SPI_SETUP1_INT_WRITE_ENABLE (1UL << 4) -#define SPI_SETUP1_CLOCK_DIVISOR(x) ((x) << 1) -#define SPI_SETUP1_CLOCK_ENABLE (1UL << 0) - -#define SPI_SETUP2_ACTIVE_EDGE_FALLING (0UL << 0) -#define SPI_SETUP2_ACTIVE_EDGE_RISING (1UL << 0) -#define SPI_SETUP2_NEGATIVE_LEVEL (0UL << 5) -#define SPI_SETUP2_POSITIVE_LEVEL (1UL << 5) -#define SPI_SETUP2_LEVEL_TRIGGER (0UL << 10) -#define SPI_SETUP2_EDGE_TRIGGER (1UL << 10) - -#define SPI_CTRL_SEN(x) ((x) << 7) -#define SPI_CTRL_WORD_SIZE(x) (((x) - 1) << 2) -#define SPI_CTRL_WR (1UL << 1) -#define SPI_CTRL_RD (1UL << 0) - -#define SPI_STATUS_WE (1UL << 1) -#define SPI_STATUS_RD (1UL << 0) - -/* use PIO for small transfers, avoiding DMA setup/teardown overhead and - * cache operations; better heuristics consider wordsize and bitrate. - */ -#define DMA_MIN_BYTES 8 - -#define SPI_RUNNING 0 -#define SPI_SHUTDOWN 1 - -struct omap1_spi100k { - struct clk *ick; - struct clk *fck; - - /* Virtual base address of the controller */ - void __iomem *base; -}; - -struct omap1_spi100k_cs { - void __iomem *base; - int word_len; -}; - -static void spi100k_enable_clock(struct spi_master *master) -{ - unsigned int val; - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - - /* enable SPI */ - val = readw(spi100k->base + SPI_SETUP1); - val |= SPI_SETUP1_CLOCK_ENABLE; - writew(val, spi100k->base + SPI_SETUP1); -} - -static void spi100k_disable_clock(struct spi_master *master) -{ - unsigned int val; - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - - /* disable SPI */ - val = readw(spi100k->base + SPI_SETUP1); - val &= ~SPI_SETUP1_CLOCK_ENABLE; - writew(val, spi100k->base + SPI_SETUP1); -} - -static void spi100k_write_data(struct spi_master *master, int len, int data) -{ - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - - /* write 16-bit word, shifting 8-bit data if necessary */ - if (len <= 8) { - data <<= 8; - len = 16; - } - - spi100k_enable_clock(master); - writew(data, spi100k->base + SPI_TX_MSB); - - writew(SPI_CTRL_SEN(0) | - SPI_CTRL_WORD_SIZE(len) | - SPI_CTRL_WR, - spi100k->base + SPI_CTRL); - - /* Wait for bit ack send change */ - while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_WE) != SPI_STATUS_WE) - ; - udelay(1000); - - spi100k_disable_clock(master); -} - -static int spi100k_read_data(struct spi_master *master, int len) -{ - int dataL; - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - - /* Always do at least 16 bits */ - if (len <= 8) - len = 16; - - spi100k_enable_clock(master); - writew(SPI_CTRL_SEN(0) | - SPI_CTRL_WORD_SIZE(len) | - SPI_CTRL_RD, - spi100k->base + SPI_CTRL); - - while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_RD) != SPI_STATUS_RD) - ; - udelay(1000); - - dataL = readw(spi100k->base + SPI_RX_LSB); - readw(spi100k->base + SPI_RX_MSB); - spi100k_disable_clock(master); - - return dataL; -} - -static void spi100k_open(struct spi_master *master) -{ - /* get control of SPI */ - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - - writew(SPI_SETUP1_INT_READ_ENABLE | - SPI_SETUP1_INT_WRITE_ENABLE | - SPI_SETUP1_CLOCK_DIVISOR(0), spi100k->base + SPI_SETUP1); - - /* configure clock and interrupts */ - writew(SPI_SETUP2_ACTIVE_EDGE_FALLING | - SPI_SETUP2_NEGATIVE_LEVEL | - SPI_SETUP2_LEVEL_TRIGGER, spi100k->base + SPI_SETUP2); -} - -static void omap1_spi100k_force_cs(struct omap1_spi100k *spi100k, int enable) -{ - if (enable) - writew(0x05fc, spi100k->base + SPI_CTRL); - else - writew(0x05fd, spi100k->base + SPI_CTRL); -} - -static unsigned -omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) -{ - struct omap1_spi100k_cs *cs = spi->controller_state; - unsigned int count, c; - int word_len; - - count = xfer->len; - c = count; - word_len = cs->word_len; - - if (word_len <= 8) { - u8 *rx; - const u8 *tx; - - rx = xfer->rx_buf; - tx = xfer->tx_buf; - do { - c -= 1; - if (xfer->tx_buf != NULL) - spi100k_write_data(spi->master, word_len, *tx++); - if (xfer->rx_buf != NULL) - *rx++ = spi100k_read_data(spi->master, word_len); - } while (c); - } else if (word_len <= 16) { - u16 *rx; - const u16 *tx; - - rx = xfer->rx_buf; - tx = xfer->tx_buf; - do { - c -= 2; - if (xfer->tx_buf != NULL) - spi100k_write_data(spi->master, word_len, *tx++); - if (xfer->rx_buf != NULL) - *rx++ = spi100k_read_data(spi->master, word_len); - } while (c); - } else if (word_len <= 32) { - u32 *rx; - const u32 *tx; - - rx = xfer->rx_buf; - tx = xfer->tx_buf; - do { - c -= 4; - if (xfer->tx_buf != NULL) - spi100k_write_data(spi->master, word_len, *tx); - if (xfer->rx_buf != NULL) - *rx = spi100k_read_data(spi->master, word_len); - } while (c); - } - return count - c; -} - -/* called only when no transfer is active to this device */ -static int omap1_spi100k_setup_transfer(struct spi_device *spi, - struct spi_transfer *t) -{ - struct omap1_spi100k *spi100k = spi_master_get_devdata(spi->master); - struct omap1_spi100k_cs *cs = spi->controller_state; - u8 word_len; - - if (t != NULL) - word_len = t->bits_per_word; - else - word_len = spi->bits_per_word; - - if (word_len > 32) - return -EINVAL; - cs->word_len = word_len; - - /* SPI init before transfer */ - writew(0x3e, spi100k->base + SPI_SETUP1); - writew(0x00, spi100k->base + SPI_STATUS); - writew(0x3e, spi100k->base + SPI_CTRL); - - return 0; -} - -/* the spi->mode bits understood by this driver: */ -#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH) - -static int omap1_spi100k_setup(struct spi_device *spi) -{ - int ret; - struct omap1_spi100k *spi100k; - struct omap1_spi100k_cs *cs = spi->controller_state; - - spi100k = spi_master_get_devdata(spi->master); - - if (!cs) { - cs = devm_kzalloc(&spi->dev, sizeof(*cs), GFP_KERNEL); - if (!cs) - return -ENOMEM; - cs->base = spi100k->base + spi->chip_select * 0x14; - spi->controller_state = cs; - } - - spi100k_open(spi->master); - - clk_prepare_enable(spi100k->ick); - clk_prepare_enable(spi100k->fck); - - ret = omap1_spi100k_setup_transfer(spi, NULL); - - clk_disable_unprepare(spi100k->ick); - clk_disable_unprepare(spi100k->fck); - - return ret; -} - -static int omap1_spi100k_transfer_one_message(struct spi_master *master, - struct spi_message *m) -{ - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - struct spi_device *spi = m->spi; - struct spi_transfer *t = NULL; - int cs_active = 0; - int status = 0; - - list_for_each_entry(t, &m->transfers, transfer_list) { - if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) { - break; - } - status = omap1_spi100k_setup_transfer(spi, t); - if (status < 0) - break; - - if (!cs_active) { - omap1_spi100k_force_cs(spi100k, 1); - cs_active = 1; - } - - if (t->len) { - unsigned count; - - count = omap1_spi100k_txrx_pio(spi, t); - m->actual_length += count; - - if (count != t->len) { - break; - } - } - - spi_transfer_delay_exec(t); - - /* ignore the "leave it on after last xfer" hint */ - - if (t->cs_change) { - omap1_spi100k_force_cs(spi100k, 0); - cs_active = 0; - } - } - - status = omap1_spi100k_setup_transfer(spi, NULL); - - if (cs_active) - omap1_spi100k_force_cs(spi100k, 0); - - m->status = status; - - spi_finalize_current_message(master); - - return status; -} - -static int omap1_spi100k_probe(struct platform_device *pdev) -{ - struct spi_master *master; - struct omap1_spi100k *spi100k; - int status = 0; - - if (!pdev->id) - return -EINVAL; - - master = spi_alloc_master(&pdev->dev, sizeof(*spi100k)); - if (master == NULL) { - dev_dbg(&pdev->dev, "master allocation failed\n"); - return -ENOMEM; - } - - if (pdev->id != -1) - master->bus_num = pdev->id; - - master->setup = omap1_spi100k_setup; - master->transfer_one_message = omap1_spi100k_transfer_one_message; - master->num_chipselect = 2; - master->mode_bits = MODEBITS; - master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); - master->min_speed_hz = OMAP1_SPI100K_MAX_FREQ/(1<<16); - master->max_speed_hz = OMAP1_SPI100K_MAX_FREQ; - master->auto_runtime_pm = true; - - spi100k = spi_master_get_devdata(master); - - /* - * The memory region base address is taken as the platform_data. - * You should allocate this with ioremap() before initializing - * the SPI. - */ - spi100k->base = (void __iomem *)dev_get_platdata(&pdev->dev); - - spi100k->ick = devm_clk_get(&pdev->dev, "ick"); - if (IS_ERR(spi100k->ick)) { - dev_dbg(&pdev->dev, "can't get spi100k_ick\n"); - status = PTR_ERR(spi100k->ick); - goto err; - } - - spi100k->fck = devm_clk_get(&pdev->dev, "fck"); - if (IS_ERR(spi100k->fck)) { - dev_dbg(&pdev->dev, "can't get spi100k_fck\n"); - status = PTR_ERR(spi100k->fck); - goto err; - } - - status = clk_prepare_enable(spi100k->ick); - if (status != 0) { - dev_err(&pdev->dev, "failed to enable ick: %d\n", status); - goto err; - } - - status = clk_prepare_enable(spi100k->fck); - if (status != 0) { - dev_err(&pdev->dev, "failed to enable fck: %d\n", status); - goto err_ick; - } - - pm_runtime_enable(&pdev->dev); - pm_runtime_set_active(&pdev->dev); - - status = devm_spi_register_master(&pdev->dev, master); - if (status < 0) - goto err_fck; - - return status; - -err_fck: - pm_runtime_disable(&pdev->dev); - clk_disable_unprepare(spi100k->fck); -err_ick: - clk_disable_unprepare(spi100k->ick); -err: - spi_master_put(master); - return status; -} - -static int omap1_spi100k_remove(struct platform_device *pdev) -{ - struct spi_master *master = platform_get_drvdata(pdev); - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - - pm_runtime_disable(&pdev->dev); - - clk_disable_unprepare(spi100k->fck); - clk_disable_unprepare(spi100k->ick); - - return 0; -} - -#ifdef CONFIG_PM -static int omap1_spi100k_runtime_suspend(struct device *dev) -{ - struct spi_master *master = dev_get_drvdata(dev); - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - - clk_disable_unprepare(spi100k->ick); - clk_disable_unprepare(spi100k->fck); - - return 0; -} - -static int omap1_spi100k_runtime_resume(struct device *dev) -{ - struct spi_master *master = dev_get_drvdata(dev); - struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - int ret; - - ret = clk_prepare_enable(spi100k->ick); - if (ret != 0) { - dev_err(dev, "Failed to enable ick: %d\n", ret); - return ret; - } - - ret = clk_prepare_enable(spi100k->fck); - if (ret != 0) { - dev_err(dev, "Failed to enable fck: %d\n", ret); - clk_disable_unprepare(spi100k->ick); - return ret; - } - - return 0; -} -#endif - -static const struct dev_pm_ops omap1_spi100k_pm = { - SET_RUNTIME_PM_OPS(omap1_spi100k_runtime_suspend, - omap1_spi100k_runtime_resume, NULL) -}; - -static struct platform_driver omap1_spi100k_driver = { - .driver = { - .name = "omap1_spi100k", - .pm = &omap1_spi100k_pm, - }, - .probe = omap1_spi100k_probe, - .remove = omap1_spi100k_remove, -}; - -module_platform_driver(omap1_spi100k_driver); - -MODULE_DESCRIPTION("OMAP7xx SPI 100k controller driver"); -MODULE_AUTHOR("Fabrice Crohas <fcrohas@gmail.com>"); -MODULE_LICENSE("GPL"); |