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authorIngo Molnar <mingo@kernel.org>2012-04-14 13:18:27 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-14 13:19:04 +0200
commit6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch)
tree021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /drivers/spi/spi-rspi.c
parent682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff)
parenta385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff)
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/spi/spi-rspi.c')
-rw-r--r--drivers/spi/spi-rspi.c521
1 files changed, 521 insertions, 0 deletions
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
new file mode 100644
index 000000000000..354f170eab95
--- /dev/null
+++ b/drivers/spi/spi-rspi.c
@@ -0,0 +1,521 @@
+/*
+ * SH RSPI driver
+ *
+ * Copyright (C) 2012 Renesas Solutions Corp.
+ *
+ * Based on spi-sh.c:
+ * Copyright (C) 2011 Renesas Solutions Corp.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/workqueue.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/spi/spi.h>
+
+#define RSPI_SPCR 0x00
+#define RSPI_SSLP 0x01
+#define RSPI_SPPCR 0x02
+#define RSPI_SPSR 0x03
+#define RSPI_SPDR 0x04
+#define RSPI_SPSCR 0x08
+#define RSPI_SPSSR 0x09
+#define RSPI_SPBR 0x0a
+#define RSPI_SPDCR 0x0b
+#define RSPI_SPCKD 0x0c
+#define RSPI_SSLND 0x0d
+#define RSPI_SPND 0x0e
+#define RSPI_SPCR2 0x0f
+#define RSPI_SPCMD0 0x10
+#define RSPI_SPCMD1 0x12
+#define RSPI_SPCMD2 0x14
+#define RSPI_SPCMD3 0x16
+#define RSPI_SPCMD4 0x18
+#define RSPI_SPCMD5 0x1a
+#define RSPI_SPCMD6 0x1c
+#define RSPI_SPCMD7 0x1e
+
+/* SPCR */
+#define SPCR_SPRIE 0x80
+#define SPCR_SPE 0x40
+#define SPCR_SPTIE 0x20
+#define SPCR_SPEIE 0x10
+#define SPCR_MSTR 0x08
+#define SPCR_MODFEN 0x04
+#define SPCR_TXMD 0x02
+#define SPCR_SPMS 0x01
+
+/* SSLP */
+#define SSLP_SSL1P 0x02
+#define SSLP_SSL0P 0x01
+
+/* SPPCR */
+#define SPPCR_MOIFE 0x20
+#define SPPCR_MOIFV 0x10
+#define SPPCR_SPOM 0x04
+#define SPPCR_SPLP2 0x02
+#define SPPCR_SPLP 0x01
+
+/* SPSR */
+#define SPSR_SPRF 0x80
+#define SPSR_SPTEF 0x20
+#define SPSR_PERF 0x08
+#define SPSR_MODF 0x04
+#define SPSR_IDLNF 0x02
+#define SPSR_OVRF 0x01
+
+/* SPSCR */
+#define SPSCR_SPSLN_MASK 0x07
+
+/* SPSSR */
+#define SPSSR_SPECM_MASK 0x70
+#define SPSSR_SPCP_MASK 0x07
+
+/* SPDCR */
+#define SPDCR_SPLW 0x20
+#define SPDCR_SPRDTD 0x10
+#define SPDCR_SLSEL1 0x08
+#define SPDCR_SLSEL0 0x04
+#define SPDCR_SLSEL_MASK 0x0c
+#define SPDCR_SPFC1 0x02
+#define SPDCR_SPFC0 0x01
+
+/* SPCKD */
+#define SPCKD_SCKDL_MASK 0x07
+
+/* SSLND */
+#define SSLND_SLNDL_MASK 0x07
+
+/* SPND */
+#define SPND_SPNDL_MASK 0x07
+
+/* SPCR2 */
+#define SPCR2_PTE 0x08
+#define SPCR2_SPIE 0x04
+#define SPCR2_SPOE 0x02
+#define SPCR2_SPPE 0x01
+
+/* SPCMDn */
+#define SPCMD_SCKDEN 0x8000
+#define SPCMD_SLNDEN 0x4000
+#define SPCMD_SPNDEN 0x2000
+#define SPCMD_LSBF 0x1000
+#define SPCMD_SPB_MASK 0x0f00
+#define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK)
+#define SPCMD_SPB_20BIT 0x0000
+#define SPCMD_SPB_24BIT 0x0100
+#define SPCMD_SPB_32BIT 0x0200
+#define SPCMD_SSLKP 0x0080
+#define SPCMD_SSLA_MASK 0x0030
+#define SPCMD_BRDV_MASK 0x000c
+#define SPCMD_CPOL 0x0002
+#define SPCMD_CPHA 0x0001
+
+struct rspi_data {
+ void __iomem *addr;
+ u32 max_speed_hz;
+ struct spi_master *master;
+ struct list_head queue;
+ struct work_struct ws;
+ wait_queue_head_t wait;
+ spinlock_t lock;
+ struct clk *clk;
+ unsigned char spsr;
+};
+
+static void rspi_write8(struct rspi_data *rspi, u8 data, u16 offset)
+{
+ iowrite8(data, rspi->addr + offset);
+}
+
+static void rspi_write16(struct rspi_data *rspi, u16 data, u16 offset)
+{
+ iowrite16(data, rspi->addr + offset);
+}
+
+static u8 rspi_read8(struct rspi_data *rspi, u16 offset)
+{
+ return ioread8(rspi->addr + offset);
+}
+
+static u16 rspi_read16(struct rspi_data *rspi, u16 offset)
+{
+ return ioread16(rspi->addr + offset);
+}
+
+static unsigned char rspi_calc_spbr(struct rspi_data *rspi)
+{
+ int tmp;
+ unsigned char spbr;
+
+ tmp = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
+ spbr = clamp(tmp, 0, 255);
+
+ return spbr;
+}
+
+static void rspi_enable_irq(struct rspi_data *rspi, u8 enable)
+{
+ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
+}
+
+static void rspi_disable_irq(struct rspi_data *rspi, u8 disable)
+{
+ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
+}
+
+static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
+ u8 enable_bit)
+{
+ int ret;
+
+ rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
+ rspi_enable_irq(rspi, enable_bit);
+ ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
+ if (ret == 0 && !(rspi->spsr & wait_mask))
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static void rspi_assert_ssl(struct rspi_data *rspi)
+{
+ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
+}
+
+static void rspi_negate_ssl(struct rspi_data *rspi)
+{
+ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
+}
+
+static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
+{
+ /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
+ rspi_write8(rspi, 0x00, RSPI_SPPCR);
+
+ /* Sets transfer bit rate */
+ rspi_write8(rspi, rspi_calc_spbr(rspi), RSPI_SPBR);
+
+ /* Sets number of frames to be used: 1 frame */
+ rspi_write8(rspi, 0x00, RSPI_SPDCR);
+
+ /* Sets RSPCK, SSL, next-access delay value */
+ rspi_write8(rspi, 0x00, RSPI_SPCKD);
+ rspi_write8(rspi, 0x00, RSPI_SSLND);
+ rspi_write8(rspi, 0x00, RSPI_SPND);
+
+ /* Sets parity, interrupt mask */
+ rspi_write8(rspi, 0x00, RSPI_SPCR2);
+
+ /* Sets SPCMD */
+ rspi_write16(rspi, SPCMD_SPB_8_TO_16(access_size) | SPCMD_SSLKP,
+ RSPI_SPCMD0);
+
+ /* Sets RSPI mode */
+ rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
+
+ return 0;
+}
+
+static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
+ struct spi_transfer *t)
+{
+ int remain = t->len;
+ u8 *data;
+
+ data = (u8 *)t->tx_buf;
+ while (remain > 0) {
+ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD,
+ RSPI_SPCR);
+
+ if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
+ dev_err(&rspi->master->dev,
+ "%s: tx empty timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+
+ rspi_write16(rspi, *data, RSPI_SPDR);
+ data++;
+ remain--;
+ }
+
+ /* Waiting for the last transmition */
+ rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
+
+ return 0;
+}
+
+static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
+ struct spi_transfer *t)
+{
+ int remain = t->len;
+ u8 *data;
+ unsigned char spsr;
+
+ spsr = rspi_read8(rspi, RSPI_SPSR);
+ if (spsr & SPSR_SPRF)
+ rspi_read16(rspi, RSPI_SPDR); /* dummy read */
+ if (spsr & SPSR_OVRF)
+ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
+ RSPI_SPCR);
+
+ data = (u8 *)t->rx_buf;
+ while (remain > 0) {
+ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD,
+ RSPI_SPCR);
+
+ if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
+ dev_err(&rspi->master->dev,
+ "%s: tx empty timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ /* dummy write for generate clock */
+ rspi_write16(rspi, 0x00, RSPI_SPDR);
+
+ if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
+ dev_err(&rspi->master->dev,
+ "%s: receive timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ /* SPDR allows 16 or 32-bit access only */
+ *data = (u8)rspi_read16(rspi, RSPI_SPDR);
+
+ data++;
+ remain--;
+ }
+
+ return 0;
+}
+
+static void rspi_work(struct work_struct *work)
+{
+ struct rspi_data *rspi = container_of(work, struct rspi_data, ws);
+ struct spi_message *mesg;
+ struct spi_transfer *t;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&rspi->lock, flags);
+ while (!list_empty(&rspi->queue)) {
+ mesg = list_entry(rspi->queue.next, struct spi_message, queue);
+ list_del_init(&mesg->queue);
+ spin_unlock_irqrestore(&rspi->lock, flags);
+
+ rspi_assert_ssl(rspi);
+
+ list_for_each_entry(t, &mesg->transfers, transfer_list) {
+ if (t->tx_buf) {
+ ret = rspi_send_pio(rspi, mesg, t);
+ if (ret < 0)
+ goto error;
+ }
+ if (t->rx_buf) {
+ ret = rspi_receive_pio(rspi, mesg, t);
+ if (ret < 0)
+ goto error;
+ }
+ mesg->actual_length += t->len;
+ }
+ rspi_negate_ssl(rspi);
+
+ mesg->status = 0;
+ mesg->complete(mesg->context);
+
+ spin_lock_irqsave(&rspi->lock, flags);
+ }
+
+ return;
+
+error:
+ mesg->status = ret;
+ mesg->complete(mesg->context);
+}
+
+static int rspi_setup(struct spi_device *spi)
+{
+ struct rspi_data *rspi = spi_master_get_devdata(spi->master);
+
+ if (!spi->bits_per_word)
+ spi->bits_per_word = 8;
+ rspi->max_speed_hz = spi->max_speed_hz;
+
+ rspi_set_config_register(rspi, 8);
+
+ return 0;
+}
+
+static int rspi_transfer(struct spi_device *spi, struct spi_message *mesg)
+{
+ struct rspi_data *rspi = spi_master_get_devdata(spi->master);
+ unsigned long flags;
+
+ mesg->actual_length = 0;
+ mesg->status = -EINPROGRESS;
+
+ spin_lock_irqsave(&rspi->lock, flags);
+ list_add_tail(&mesg->queue, &rspi->queue);
+ schedule_work(&rspi->ws);
+ spin_unlock_irqrestore(&rspi->lock, flags);
+
+ return 0;
+}
+
+static void rspi_cleanup(struct spi_device *spi)
+{
+}
+
+static irqreturn_t rspi_irq(int irq, void *_sr)
+{
+ struct rspi_data *rspi = (struct rspi_data *)_sr;
+ unsigned long spsr;
+ irqreturn_t ret = IRQ_NONE;
+ unsigned char disable_irq = 0;
+
+ rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
+ if (spsr & SPSR_SPRF)
+ disable_irq |= SPCR_SPRIE;
+ if (spsr & SPSR_SPTEF)
+ disable_irq |= SPCR_SPTIE;
+
+ if (disable_irq) {
+ ret = IRQ_HANDLED;
+ rspi_disable_irq(rspi, disable_irq);
+ wake_up(&rspi->wait);
+ }
+
+ return ret;
+}
+
+static int __devexit rspi_remove(struct platform_device *pdev)
+{
+ struct rspi_data *rspi = dev_get_drvdata(&pdev->dev);
+
+ spi_unregister_master(rspi->master);
+ free_irq(platform_get_irq(pdev, 0), rspi);
+ clk_put(rspi->clk);
+ iounmap(rspi->addr);
+ spi_master_put(rspi->master);
+
+ return 0;
+}
+
+static int __devinit rspi_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct spi_master *master;
+ struct rspi_data *rspi;
+ int ret, irq;
+ char clk_name[16];
+
+ /* get base addr */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (unlikely(res == NULL)) {
+ dev_err(&pdev->dev, "invalid resource\n");
+ return -EINVAL;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "platform_get_irq error\n");
+ return -ENODEV;
+ }
+
+ master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
+ if (master == NULL) {
+ dev_err(&pdev->dev, "spi_alloc_master error.\n");
+ return -ENOMEM;
+ }
+
+ rspi = spi_master_get_devdata(master);
+ dev_set_drvdata(&pdev->dev, rspi);
+
+ rspi->master = master;
+ rspi->addr = ioremap(res->start, resource_size(res));
+ if (rspi->addr == NULL) {
+ dev_err(&pdev->dev, "ioremap error.\n");
+ ret = -ENOMEM;
+ goto error1;
+ }
+
+ snprintf(clk_name, sizeof(clk_name), "rspi%d", pdev->id);
+ rspi->clk = clk_get(&pdev->dev, clk_name);
+ if (IS_ERR(rspi->clk)) {
+ dev_err(&pdev->dev, "cannot get clock\n");
+ ret = PTR_ERR(rspi->clk);
+ goto error2;
+ }
+ clk_enable(rspi->clk);
+
+ INIT_LIST_HEAD(&rspi->queue);
+ spin_lock_init(&rspi->lock);
+ INIT_WORK(&rspi->ws, rspi_work);
+ init_waitqueue_head(&rspi->wait);
+
+ master->num_chipselect = 2;
+ master->bus_num = pdev->id;
+ master->setup = rspi_setup;
+ master->transfer = rspi_transfer;
+ master->cleanup = rspi_cleanup;
+
+ ret = request_irq(irq, rspi_irq, 0, dev_name(&pdev->dev), rspi);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "request_irq error\n");
+ goto error3;
+ }
+
+ ret = spi_register_master(master);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "spi_register_master error.\n");
+ goto error4;
+ }
+
+ dev_info(&pdev->dev, "probed\n");
+
+ return 0;
+
+error4:
+ free_irq(irq, rspi);
+error3:
+ clk_put(rspi->clk);
+error2:
+ iounmap(rspi->addr);
+error1:
+ spi_master_put(master);
+
+ return ret;
+}
+
+static struct platform_driver rspi_driver = {
+ .probe = rspi_probe,
+ .remove = __devexit_p(rspi_remove),
+ .driver = {
+ .name = "rspi",
+ .owner = THIS_MODULE,
+ },
+};
+module_platform_driver(rspi_driver);
+
+MODULE_DESCRIPTION("Renesas RSPI bus driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Yoshihiro Shimoda");
+MODULE_ALIAS("platform:rspi");