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authorGrant Likely <grant.likely@secretlab.ca>2011-06-06 09:16:30 +0200
committerGrant Likely <grant.likely@secretlab.ca>2011-06-06 09:16:30 +0200
commitca632f556697d45d67ed5cada7cedf3ddfe0db4b (patch)
treef393534b929abb32813ea5c495f1ac6d93a10d1d /drivers/spi/omap_uwire.c
parentspi/bitbang: initialize bits_per_word as specified by spi message (diff)
downloadlinux-ca632f556697d45d67ed5cada7cedf3ddfe0db4b.tar.xz
linux-ca632f556697d45d67ed5cada7cedf3ddfe0db4b.zip
spi: reorganize drivers
Sort the SPI makefile and enforce the naming convention spi_*.c for spi drivers. This change also rolls the contents of atmel_spi.h into the .c file since there is only one user of that particular include file. v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be be the predominant pattern for subsystem prefixes. - Clean up filenames in Kconfig and header comment blocks Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/spi/omap_uwire.c')
-rw-r--r--drivers/spi/omap_uwire.c593
1 files changed, 0 insertions, 593 deletions
diff --git a/drivers/spi/omap_uwire.c b/drivers/spi/omap_uwire.c
deleted file mode 100644
index 160d3266205f..000000000000
--- a/drivers/spi/omap_uwire.c
+++ /dev/null
@@ -1,593 +0,0 @@
-/*
- * omap_uwire.c -- MicroWire interface driver for OMAP
- *
- * Copyright 2003 MontaVista Software Inc. <source@mvista.com>
- *
- * Ported to 2.6 OMAP uwire interface.
- * Copyright (C) 2004 Texas Instruments.
- *
- * Generalization patches by Juha Yrjola <juha.yrjola@nokia.com>
- *
- * Copyright (C) 2005 David Brownell (ported to 2.6 SPI interface)
- * Copyright (C) 2006 Nokia
- *
- * Many updates by Imre Deak <imre.deak@nokia.com>
- *
- * 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 SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- * 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.,
- * 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/delay.h>
-#include <linux/platform_device.h>
-#include <linux/workqueue.h>
-#include <linux/interrupt.h>
-#include <linux/err.h>
-#include <linux/clk.h>
-#include <linux/slab.h>
-
-#include <linux/spi/spi.h>
-#include <linux/spi/spi_bitbang.h>
-
-#include <asm/system.h>
-#include <asm/irq.h>
-#include <mach/hardware.h>
-#include <asm/io.h>
-#include <asm/mach-types.h>
-
-#include <plat/mux.h>
-#include <plat/omap7xx.h> /* OMAP7XX_IO_CONF registers */
-
-
-/* FIXME address is now a platform device resource,
- * and irqs should show there too...
- */
-#define UWIRE_BASE_PHYS 0xFFFB3000
-
-/* uWire Registers: */
-#define UWIRE_IO_SIZE 0x20
-#define UWIRE_TDR 0x00
-#define UWIRE_RDR 0x00
-#define UWIRE_CSR 0x01
-#define UWIRE_SR1 0x02
-#define UWIRE_SR2 0x03
-#define UWIRE_SR3 0x04
-#define UWIRE_SR4 0x05
-#define UWIRE_SR5 0x06
-
-/* CSR bits */
-#define RDRB (1 << 15)
-#define CSRB (1 << 14)
-#define START (1 << 13)
-#define CS_CMD (1 << 12)
-
-/* SR1 or SR2 bits */
-#define UWIRE_READ_FALLING_EDGE 0x0001
-#define UWIRE_READ_RISING_EDGE 0x0000
-#define UWIRE_WRITE_FALLING_EDGE 0x0000
-#define UWIRE_WRITE_RISING_EDGE 0x0002
-#define UWIRE_CS_ACTIVE_LOW 0x0000
-#define UWIRE_CS_ACTIVE_HIGH 0x0004
-#define UWIRE_FREQ_DIV_2 0x0000
-#define UWIRE_FREQ_DIV_4 0x0008
-#define UWIRE_FREQ_DIV_8 0x0010
-#define UWIRE_CHK_READY 0x0020
-#define UWIRE_CLK_INVERTED 0x0040
-
-
-struct uwire_spi {
- struct spi_bitbang bitbang;
- struct clk *ck;
-};
-
-struct uwire_state {
- unsigned bits_per_word;
- unsigned div1_idx;
-};
-
-/* REVISIT compile time constant for idx_shift? */
-/*
- * Or, put it in a structure which is used throughout the driver;
- * that avoids having to issue two loads for each bit of static data.
- */
-static unsigned int uwire_idx_shift;
-static void __iomem *uwire_base;
-
-static inline void uwire_write_reg(int idx, u16 val)
-{
- __raw_writew(val, uwire_base + (idx << uwire_idx_shift));
-}
-
-static inline u16 uwire_read_reg(int idx)
-{
- return __raw_readw(uwire_base + (idx << uwire_idx_shift));
-}
-
-static inline void omap_uwire_configure_mode(u8 cs, unsigned long flags)
-{
- u16 w, val = 0;
- int shift, reg;
-
- if (flags & UWIRE_CLK_INVERTED)
- val ^= 0x03;
- val = flags & 0x3f;
- if (cs & 1)
- shift = 6;
- else
- shift = 0;
- if (cs <= 1)
- reg = UWIRE_SR1;
- else
- reg = UWIRE_SR2;
-
- w = uwire_read_reg(reg);
- w &= ~(0x3f << shift);
- w |= val << shift;
- uwire_write_reg(reg, w);
-}
-
-static int wait_uwire_csr_flag(u16 mask, u16 val, int might_not_catch)
-{
- u16 w;
- int c = 0;
- unsigned long max_jiffies = jiffies + HZ;
-
- for (;;) {
- w = uwire_read_reg(UWIRE_CSR);
- if ((w & mask) == val)
- break;
- if (time_after(jiffies, max_jiffies)) {
- printk(KERN_ERR "%s: timeout. reg=%#06x "
- "mask=%#06x val=%#06x\n",
- __func__, w, mask, val);
- return -1;
- }
- c++;
- if (might_not_catch && c > 64)
- break;
- }
- return 0;
-}
-
-static void uwire_set_clk1_div(int div1_idx)
-{
- u16 w;
-
- w = uwire_read_reg(UWIRE_SR3);
- w &= ~(0x03 << 1);
- w |= div1_idx << 1;
- uwire_write_reg(UWIRE_SR3, w);
-}
-
-static void uwire_chipselect(struct spi_device *spi, int value)
-{
- struct uwire_state *ust = spi->controller_state;
- u16 w;
- int old_cs;
-
-
- BUG_ON(wait_uwire_csr_flag(CSRB, 0, 0));
-
- w = uwire_read_reg(UWIRE_CSR);
- old_cs = (w >> 10) & 0x03;
- if (value == BITBANG_CS_INACTIVE || old_cs != spi->chip_select) {
- /* Deselect this CS, or the previous CS */
- w &= ~CS_CMD;
- uwire_write_reg(UWIRE_CSR, w);
- }
- /* activate specfied chipselect */
- if (value == BITBANG_CS_ACTIVE) {
- uwire_set_clk1_div(ust->div1_idx);
- /* invert clock? */
- if (spi->mode & SPI_CPOL)
- uwire_write_reg(UWIRE_SR4, 1);
- else
- uwire_write_reg(UWIRE_SR4, 0);
-
- w = spi->chip_select << 10;
- w |= CS_CMD;
- uwire_write_reg(UWIRE_CSR, w);
- }
-}
-
-static int uwire_txrx(struct spi_device *spi, struct spi_transfer *t)
-{
- struct uwire_state *ust = spi->controller_state;
- unsigned len = t->len;
- unsigned bits = ust->bits_per_word;
- unsigned bytes;
- u16 val, w;
- int status = 0;
-
- if (!t->tx_buf && !t->rx_buf)
- return 0;
-
- /* Microwire doesn't read and write concurrently */
- if (t->tx_buf && t->rx_buf)
- return -EPERM;
-
- w = spi->chip_select << 10;
- w |= CS_CMD;
-
- if (t->tx_buf) {
- const u8 *buf = t->tx_buf;
-
- /* NOTE: DMA could be used for TX transfers */
-
- /* write one or two bytes at a time */
- while (len >= 1) {
- /* tx bit 15 is first sent; we byteswap multibyte words
- * (msb-first) on the way out from memory.
- */
- val = *buf++;
- if (bits > 8) {
- bytes = 2;
- val |= *buf++ << 8;
- } else
- bytes = 1;
- val <<= 16 - bits;
-
-#ifdef VERBOSE
- pr_debug("%s: write-%d =%04x\n",
- dev_name(&spi->dev), bits, val);
-#endif
- if (wait_uwire_csr_flag(CSRB, 0, 0))
- goto eio;
-
- uwire_write_reg(UWIRE_TDR, val);
-
- /* start write */
- val = START | w | (bits << 5);
-
- uwire_write_reg(UWIRE_CSR, val);
- len -= bytes;
-
- /* Wait till write actually starts.
- * This is needed with MPU clock 60+ MHz.
- * REVISIT: we may not have time to catch it...
- */
- if (wait_uwire_csr_flag(CSRB, CSRB, 1))
- goto eio;
-
- status += bytes;
- }
-
- /* REVISIT: save this for later to get more i/o overlap */
- if (wait_uwire_csr_flag(CSRB, 0, 0))
- goto eio;
-
- } else if (t->rx_buf) {
- u8 *buf = t->rx_buf;
-
- /* read one or two bytes at a time */
- while (len) {
- if (bits > 8) {
- bytes = 2;
- } else
- bytes = 1;
-
- /* start read */
- val = START | w | (bits << 0);
- uwire_write_reg(UWIRE_CSR, val);
- len -= bytes;
-
- /* Wait till read actually starts */
- (void) wait_uwire_csr_flag(CSRB, CSRB, 1);
-
- if (wait_uwire_csr_flag(RDRB | CSRB,
- RDRB, 0))
- goto eio;
-
- /* rx bit 0 is last received; multibyte words will
- * be properly byteswapped on the way to memory.
- */
- val = uwire_read_reg(UWIRE_RDR);
- val &= (1 << bits) - 1;
- *buf++ = (u8) val;
- if (bytes == 2)
- *buf++ = val >> 8;
- status += bytes;
-#ifdef VERBOSE
- pr_debug("%s: read-%d =%04x\n",
- dev_name(&spi->dev), bits, val);
-#endif
-
- }
- }
- return status;
-eio:
- return -EIO;
-}
-
-static int uwire_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
-{
- struct uwire_state *ust = spi->controller_state;
- struct uwire_spi *uwire;
- unsigned flags = 0;
- unsigned bits;
- unsigned hz;
- unsigned long rate;
- int div1_idx;
- int div1;
- int div2;
- int status;
-
- uwire = spi_master_get_devdata(spi->master);
-
- if (spi->chip_select > 3) {
- pr_debug("%s: cs%d?\n", dev_name(&spi->dev), spi->chip_select);
- status = -ENODEV;
- goto done;
- }
-
- bits = spi->bits_per_word;
- if (t != NULL && t->bits_per_word)
- bits = t->bits_per_word;
-
- if (bits > 16) {
- pr_debug("%s: wordsize %d?\n", dev_name(&spi->dev), bits);
- status = -ENODEV;
- goto done;
- }
- ust->bits_per_word = bits;
-
- /* mode 0..3, clock inverted separately;
- * standard nCS signaling;
- * don't treat DI=high as "not ready"
- */
- if (spi->mode & SPI_CS_HIGH)
- flags |= UWIRE_CS_ACTIVE_HIGH;
-
- if (spi->mode & SPI_CPOL)
- flags |= UWIRE_CLK_INVERTED;
-
- switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
- case SPI_MODE_0:
- case SPI_MODE_3:
- flags |= UWIRE_WRITE_FALLING_EDGE | UWIRE_READ_RISING_EDGE;
- break;
- case SPI_MODE_1:
- case SPI_MODE_2:
- flags |= UWIRE_WRITE_RISING_EDGE | UWIRE_READ_FALLING_EDGE;
- break;
- }
-
- /* assume it's already enabled */
- rate = clk_get_rate(uwire->ck);
-
- hz = spi->max_speed_hz;
- if (t != NULL && t->speed_hz)
- hz = t->speed_hz;
-
- if (!hz) {
- pr_debug("%s: zero speed?\n", dev_name(&spi->dev));
- status = -EINVAL;
- goto done;
- }
-
- /* F_INT = mpu_xor_clk / DIV1 */
- for (div1_idx = 0; div1_idx < 4; div1_idx++) {
- switch (div1_idx) {
- case 0:
- div1 = 2;
- break;
- case 1:
- div1 = 4;
- break;
- case 2:
- div1 = 7;
- break;
- default:
- case 3:
- div1 = 10;
- break;
- }
- div2 = (rate / div1 + hz - 1) / hz;
- if (div2 <= 8)
- break;
- }
- if (div1_idx == 4) {
- pr_debug("%s: lowest clock %ld, need %d\n",
- dev_name(&spi->dev), rate / 10 / 8, hz);
- status = -EDOM;
- goto done;
- }
-
- /* we have to cache this and reset in uwire_chipselect as this is a
- * global parameter and another uwire device can change it under
- * us */
- ust->div1_idx = div1_idx;
- uwire_set_clk1_div(div1_idx);
-
- rate /= div1;
-
- switch (div2) {
- case 0:
- case 1:
- case 2:
- flags |= UWIRE_FREQ_DIV_2;
- rate /= 2;
- break;
- case 3:
- case 4:
- flags |= UWIRE_FREQ_DIV_4;
- rate /= 4;
- break;
- case 5:
- case 6:
- case 7:
- case 8:
- flags |= UWIRE_FREQ_DIV_8;
- rate /= 8;
- break;
- }
- omap_uwire_configure_mode(spi->chip_select, flags);
- pr_debug("%s: uwire flags %02x, armxor %lu KHz, SCK %lu KHz\n",
- __func__, flags,
- clk_get_rate(uwire->ck) / 1000,
- rate / 1000);
- status = 0;
-done:
- return status;
-}
-
-static int uwire_setup(struct spi_device *spi)
-{
- struct uwire_state *ust = spi->controller_state;
-
- if (ust == NULL) {
- ust = kzalloc(sizeof(*ust), GFP_KERNEL);
- if (ust == NULL)
- return -ENOMEM;
- spi->controller_state = ust;
- }
-
- return uwire_setup_transfer(spi, NULL);
-}
-
-static void uwire_cleanup(struct spi_device *spi)
-{
- kfree(spi->controller_state);
-}
-
-static void uwire_off(struct uwire_spi *uwire)
-{
- uwire_write_reg(UWIRE_SR3, 0);
- clk_disable(uwire->ck);
- clk_put(uwire->ck);
- spi_master_put(uwire->bitbang.master);
-}
-
-static int __init uwire_probe(struct platform_device *pdev)
-{
- struct spi_master *master;
- struct uwire_spi *uwire;
- int status;
-
- master = spi_alloc_master(&pdev->dev, sizeof *uwire);
- if (!master)
- return -ENODEV;
-
- uwire = spi_master_get_devdata(master);
-
- uwire_base = ioremap(UWIRE_BASE_PHYS, UWIRE_IO_SIZE);
- if (!uwire_base) {
- dev_dbg(&pdev->dev, "can't ioremap UWIRE\n");
- spi_master_put(master);
- return -ENOMEM;
- }
-
- dev_set_drvdata(&pdev->dev, uwire);
-
- uwire->ck = clk_get(&pdev->dev, "fck");
- if (IS_ERR(uwire->ck)) {
- status = PTR_ERR(uwire->ck);
- dev_dbg(&pdev->dev, "no functional clock?\n");
- spi_master_put(master);
- return status;
- }
- clk_enable(uwire->ck);
-
- if (cpu_is_omap7xx())
- uwire_idx_shift = 1;
- else
- uwire_idx_shift = 2;
-
- uwire_write_reg(UWIRE_SR3, 1);
-
- /* the spi->mode bits understood by this driver: */
- master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
-
- master->flags = SPI_MASTER_HALF_DUPLEX;
-
- master->bus_num = 2; /* "official" */
- master->num_chipselect = 4;
- master->setup = uwire_setup;
- master->cleanup = uwire_cleanup;
-
- uwire->bitbang.master = master;
- uwire->bitbang.chipselect = uwire_chipselect;
- uwire->bitbang.setup_transfer = uwire_setup_transfer;
- uwire->bitbang.txrx_bufs = uwire_txrx;
-
- status = spi_bitbang_start(&uwire->bitbang);
- if (status < 0) {
- uwire_off(uwire);
- iounmap(uwire_base);
- }
- return status;
-}
-
-static int __exit uwire_remove(struct platform_device *pdev)
-{
- struct uwire_spi *uwire = dev_get_drvdata(&pdev->dev);
- int status;
-
- // FIXME remove all child devices, somewhere ...
-
- status = spi_bitbang_stop(&uwire->bitbang);
- uwire_off(uwire);
- iounmap(uwire_base);
- return status;
-}
-
-/* work with hotplug and coldplug */
-MODULE_ALIAS("platform:omap_uwire");
-
-static struct platform_driver uwire_driver = {
- .driver = {
- .name = "omap_uwire",
- .owner = THIS_MODULE,
- },
- .remove = __exit_p(uwire_remove),
- // suspend ... unuse ck
- // resume ... use ck
-};
-
-static int __init omap_uwire_init(void)
-{
- /* FIXME move these into the relevant board init code. also, include
- * H3 support; it uses tsc2101 like H2 (on a different chipselect).
- */
-
- if (machine_is_omap_h2()) {
- /* defaults: W21 SDO, U18 SDI, V19 SCL */
- omap_cfg_reg(N14_1610_UWIRE_CS0);
- omap_cfg_reg(N15_1610_UWIRE_CS1);
- }
- if (machine_is_omap_perseus2()) {
- /* configure pins: MPU_UW_nSCS1, MPU_UW_SDO, MPU_UW_SCLK */
- int val = omap_readl(OMAP7XX_IO_CONF_9) & ~0x00EEE000;
- omap_writel(val | 0x00AAA000, OMAP7XX_IO_CONF_9);
- }
-
- return platform_driver_probe(&uwire_driver, uwire_probe);
-}
-
-static void __exit omap_uwire_exit(void)
-{
- platform_driver_unregister(&uwire_driver);
-}
-
-subsys_initcall(omap_uwire_init);
-module_exit(omap_uwire_exit);
-
-MODULE_LICENSE("GPL");
-