Re: [PATCH] spi: add support for SuperH SPI

Grant Likely
2011-02-16T02:59:50Z

On Tue, Feb 15, 2011 at 10:30:32AM +0900, Yoshihiro Shimoda wrote:
> The SH7757 has SPI0 module. This patch supports it.
>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Merged, thanks. I made a few minor edits on style issues and to add
the __devinit/__devexit annotations to the probe/remove functions.
Please give it a spin to make sure I haven't broken anything when it
appears in my spi/next branch on git://git.secretlab.ca/git/linux-2.6
(sometime in the next 6 hours).

g.

> ---
> drivers/spi/Kconfig | 6 +
> drivers/spi/Makefile | 1 +
> drivers/spi/spi_sh.c | 547 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 554 insertions(+), 0 deletions(-)
> create mode 100644 drivers/spi/spi_sh.c
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index bb233a9..1532d2c 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -330,6 +330,12 @@ config SPI_SH_MSIOF
> help
> SPI driver for SuperH MSIOF blocks.
>
> +config SPI_SH
> + tristate "SuperH SPI controller"
> + depends on SUPERH
> + help
> + SPI driver for SuperH SPI blocks.
> +
> config SPI_SH_SCI
> tristate "SuperH SCI SPI controller"
> depends on SUPERH
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index 86d1b5f..068465f 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -48,6 +48,7 @@ obj-$(CONFIG_SPI_TXX9) += spi_txx9.o
> obj-$(CONFIG_SPI_XILINX) += xilinx_spi.o
> obj-$(CONFIG_SPI_SH_SCI) += spi_sh_sci.o
> obj-$(CONFIG_SPI_SH_MSIOF) += spi_sh_msiof.o
> +obj-$(CONFIG_SPI_SH) += spi_sh.o
> obj-$(CONFIG_SPI_STMP3XXX) += spi_stmp.o
> obj-$(CONFIG_SPI_NUC900) += spi_nuc900.o
>
> diff --git a/drivers/spi/spi_sh.c b/drivers/spi/spi_sh.c
> new file mode 100644
> index 0000000..247ef0b
> --- /dev/null
> +++ b/drivers/spi/spi_sh.c
> @@ -0,0 +1,547 @@
> +/*
> + * SH SPI bus driver
> + *
> + * Copyright (C) 2011 Renesas Solutions Corp.
> + *
> + * Based on pxa2xx_spi.c:
> + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
> + *
> + * 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/timer.h>
> +#include <linux/delay.h>
> +#include <linux/list.h>
> +#include <linux/workqueue.h>
> +#include <linux/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/io.h>
> +#include <linux/spi/spi.h>
> +
> +#define DRIVER_VERSION "2011-02-02"
> +
> +#define SPI_SH_TBR 0x00
> +#define SPI_SH_RBR 0x00
> +#define SPI_SH_CR1 0x08
> +#define SPI_SH_CR2 0x10
> +#define SPI_SH_CR3 0x18
> +#define SPI_SH_CR4 0x20
> +#define SPI_SH_CR5 0x28
> +
> +/* CR1 */
> +#define SPI_SH_TBE 0x80
> +#define SPI_SH_TBF 0x40
> +#define SPI_SH_RBE 0x20
> +#define SPI_SH_RBF 0x10
> +#define SPI_SH_PFONRD 0x08
> +#define SPI_SH_SSDB 0x04
> +#define SPI_SH_SSD 0x02
> +#define SPI_SH_SSA 0x01
> +
> +/* CR2 */
> +#define SPI_SH_RSTF 0x80
> +#define SPI_SH_LOOPBK 0x40
> +#define SPI_SH_CPOL 0x20
> +#define SPI_SH_CPHA 0x10
> +#define SPI_SH_L1M0 0x08
> +
> +/* CR3 */
> +#define SPI_SH_MAX_BYTE 0xFF
> +
> +/* CR4 */
> +#define SPI_SH_TBEI 0x80
> +#define SPI_SH_TBFI 0x40
> +#define SPI_SH_RBEI 0x20
> +#define SPI_SH_RBFI 0x10
> +#define SPI_SH_WPABRT 0x04
> +#define SPI_SH_SSS 0x01
> +
> +/* CR8 */
> +#define SPI_SH_P1L0 0x80
> +#define SPI_SH_PP1L0 0x40
> +#define SPI_SH_MUXI 0x20
> +#define SPI_SH_MUXIRQ 0x10
> +
> +#define SPI_SH_FIFO_SIZE 32
> +#define SPI_SH_SEND_TIMEOUT (3 * HZ)
> +#define SPI_SH_RECEIVE_TIMEOUT (HZ >> 3)
> +
> +#undef DEBUG
> +
> +struct spi_sh_data {
> + void __iomem *addr;
> + int irq;
> + struct spi_master *master;
> + struct list_head queue;
> + struct workqueue_struct *workqueue;
> + struct work_struct ws;
> + unsigned long cr1;
> + wait_queue_head_t wait;
> + spinlock_t lock;
> +};
> +
> +static void spi_sh_write(struct spi_sh_data *ss, unsigned long data,
> + unsigned long offset)
> +{
> + writel(data, ss->addr + offset);
> +}
> +
> +static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset)
> +{
> + return readl(ss->addr + offset);
> +}
> +
> +static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val,
> + unsigned long offset)
> +{
> + unsigned long tmp;
> +
> + tmp = spi_sh_read(ss, offset);
> + tmp |= val;
> + spi_sh_write(ss, tmp, offset);
> +}
> +
> +static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val,
> + unsigned long offset)
> +{
> + unsigned long tmp;
> +
> + tmp = spi_sh_read(ss, offset);
> + tmp &= ~val;
> + spi_sh_write(ss, tmp, offset);
> +}
> +
> +static void clear_fifo(struct spi_sh_data *ss)
> +{
> + spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
> + spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
> +}
> +
> +static int wait_receive_buffer(struct spi_sh_data *ss)
> +{
> + int timeout = 100000;
> +
> + while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
> + udelay(10);
> + if (timeout-- < 0)
> + return -ETIMEDOUT;
> + }
> + return 0;
> +}
> +
> +static int wait_write_buffer_empty(struct spi_sh_data *ss)
> +{
> + int timeout = 100000;
> +
> + while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) {
> + udelay(10);
> + if (timeout-- < 0)
> + return -ETIMEDOUT;
> + }
> + return 0;
> +}
> +
> +static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg,
> + struct spi_transfer *t)
> +{
> + int i, retval = 0;
> + int remain = t->len;
> + int cur_len;
> + unsigned char *data;
> + unsigned long tmp;
> + long ret;
> +
> + if (t->len)
> + spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
> +
> + data = (unsigned char *)t->tx_buf;
> + while (remain > 0) {
> + cur_len = min(SPI_SH_FIFO_SIZE, remain);
> + for (i = 0; i < cur_len &&
> + !(spi_sh_read(ss, SPI_SH_CR4) &
> + SPI_SH_WPABRT) &&
> + !(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF);
> + i++)
> + spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR);
> +
> + if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) {
> + /* Abort SPI operation */
> + spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4);
> + retval = -EIO;
> + break;
> + }
> +
> + cur_len = i;
> +
> + remain -= cur_len;
> + data += cur_len;
> +
> + if (remain > 0) {
> + ss->cr1 &= ~SPI_SH_TBE;
> + spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
> + ret = wait_event_interruptible_timeout(ss->wait,
> + ss->cr1 & SPI_SH_TBE,
> + SPI_SH_SEND_TIMEOUT);
> + if (ret = 0 && !(ss->cr1 & SPI_SH_TBE)) {
> + printk(KERN_ERR "%s: timeout\n", __func__);
> + return -ETIMEDOUT;
> + }
> + }
> + }
> +
> + if (list_is_last(&t->transfer_list, &mesg->transfers)) {
> + tmp = spi_sh_read(ss, SPI_SH_CR1);
> + tmp = tmp & ~(SPI_SH_SSD | SPI_SH_SSDB);
> + spi_sh_write(ss, tmp, SPI_SH_CR1);
> + spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
> +
> + ss->cr1 &= ~SPI_SH_TBE;
> + spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
> + ret = wait_event_interruptible_timeout(ss->wait,
> + ss->cr1 & SPI_SH_TBE,
> + SPI_SH_SEND_TIMEOUT);
> + if (ret = 0 && (ss->cr1 & SPI_SH_TBE)) {
> + printk(KERN_ERR "%s: timeout\n", __func__);
> + return -ETIMEDOUT;
> + }
> + }
> +
> + return retval;
> +}
> +
> +static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg,
> + struct spi_transfer *t)
> +{
> + int i;
> + int remain = t->len;
> + int cur_len;
> + unsigned char *data;
> + unsigned long tmp;
> + long ret;
> +
> + if (t->len > SPI_SH_MAX_BYTE)
> + spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3);
> + else
> + spi_sh_write(ss, t->len, SPI_SH_CR3);
> +
> + tmp = spi_sh_read(ss, SPI_SH_CR1);
> + tmp = tmp & ~(SPI_SH_SSD | SPI_SH_SSDB);
> + spi_sh_write(ss, tmp, SPI_SH_CR1);
> + spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
> +
> + wait_write_buffer_empty(ss);
> +
> + data = (unsigned char *)t->rx_buf;
> + while (remain > 0) {
> + if (remain >= SPI_SH_FIFO_SIZE) {
> + ss->cr1 &= ~SPI_SH_RBF;
> + spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
> + ret = wait_event_interruptible_timeout(ss->wait,
> + ss->cr1 & SPI_SH_RBF,
> + SPI_SH_RECEIVE_TIMEOUT);
> + if (ret = 0 &&
> + spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
> + printk(KERN_ERR "%s: timeout\n", __func__);
> + return -ETIMEDOUT;
> + }
> + }
> +
> + cur_len = min(SPI_SH_FIFO_SIZE, remain);
> + for (i = 0; i < cur_len; i++) {
> + if (wait_receive_buffer(ss))
> + break;
> + data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR);
> + }
> +
> + remain -= cur_len;
> + data += cur_len;
> + }
> +
> + /* deassert CS when SPI is receiving. */
> + if (t->len > SPI_SH_MAX_BYTE) {
> + clear_fifo(ss);
> + spi_sh_write(ss, 1, SPI_SH_CR3);
> + } else {
> + spi_sh_write(ss, 0, SPI_SH_CR3);
> + }
> +
> + return 0;
> +}
> +
> +static void spi_sh_work(struct work_struct *work)
> +{
> + struct spi_sh_data *ss = container_of(work, struct spi_sh_data, ws);
> + struct spi_message *mesg;
> + struct spi_transfer *t;
> + unsigned long flags;
> + int ret;
> +
> + pr_debug("%s: enter\n", __func__);
> +
> + spin_lock_irqsave(&ss->lock, flags);
> + while (!list_empty(&ss->queue)) {
> + mesg = list_entry(ss->queue.next, struct spi_message, queue);
> + list_del_init(&mesg->queue);
> +
> + spin_unlock_irqrestore(&ss->lock, flags);
> + list_for_each_entry(t, &mesg->transfers, transfer_list) {
> + pr_debug("tx_buf = %p, rx_buf = %p\n",
> + t->tx_buf, t->rx_buf);
> + pr_debug("len = %d, delay_usecs = %d\n",
> + t->len, t->delay_usecs);
> +
> + if (t->tx_buf) {
> + ret = spi_sh_send(ss, mesg, t);
> + if (ret < 0)
> + goto error;
> + }
> + if (t->rx_buf) {
> + ret = spi_sh_receive(ss, mesg, t);
> + if (ret < 0)
> + goto error;
> + }
> + mesg->actual_length += t->len;
> + }
> + spin_lock_irqsave(&ss->lock, flags);
> +
> + mesg->status = 0;
> + mesg->complete(mesg->context);
> + }
> +
> + clear_fifo(ss);
> + spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1);
> + udelay(100);
> +
> + spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
> + SPI_SH_CR1);
> +
> + clear_fifo(ss);
> +
> + spin_unlock_irqrestore(&ss->lock, flags);
> +
> + return;
> +
> +error:
> + mesg->status = ret;
> + mesg->complete(mesg->context);
> +
> + spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
> + SPI_SH_CR1);
> + clear_fifo(ss);
> +
> +}
> +
> +static int spi_sh_setup(struct spi_device *spi)
> +{
> + struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
> +
> + if (!spi->bits_per_word)
> + spi->bits_per_word = 8;
> +
> + pr_debug("%s: enter\n", __func__);
> +
> + spi_sh_write(ss, 0xfe, SPI_SH_CR1); /* SPI sycle stop */
> + spi_sh_write(ss, 0x00, SPI_SH_CR1); /* CR1 init */
> + spi_sh_write(ss, 0x00, SPI_SH_CR3); /* CR3 init */
> +
> + clear_fifo(ss);
> +
> + /* 1/8 clock */
> + spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2);
> + udelay(10);
> +
> + return 0;
> +}
> +
> +static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg)
> +{
> + struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
> + unsigned long flags;
> +
> + pr_debug("%s: enter\n", __func__);
> + pr_debug("\tmode = %02x\n", spi->mode);
> +
> + spin_lock_irqsave(&ss->lock, flags);
> +
> + mesg->actual_length = 0;
> + mesg->status = -EINPROGRESS;
> +
> + spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
> +
> + list_add_tail(&mesg->queue, &ss->queue);
> + queue_work(ss->workqueue, &ss->ws);
> +
> + spin_unlock_irqrestore(&ss->lock, flags);
> +
> + return 0;
> +}
> +
> +static void spi_sh_cleanup(struct spi_device *spi)
> +{
> + struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
> +
> + pr_debug("%s: enter\n", __func__);
> +
> + spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
> + SPI_SH_CR1);
> +}
> +
> +static irqreturn_t spi_sh_irq(int irq, void *_ss)
> +{
> + struct spi_sh_data *ss = (struct spi_sh_data *)_ss;
> + unsigned long cr1;
> +
> + cr1 = spi_sh_read(ss, SPI_SH_CR1);
> + if (cr1 & SPI_SH_TBE)
> + ss->cr1 |= SPI_SH_TBE;
> + if (cr1 & SPI_SH_TBF)
> + ss->cr1 |= SPI_SH_TBF;
> + if (cr1 & SPI_SH_RBE)
> + ss->cr1 |= SPI_SH_RBE;
> + if (cr1 & SPI_SH_RBF)
> + ss->cr1 |= SPI_SH_RBF;
> +
> + if (ss->cr1) {
> + spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4);
> + wake_up(&ss->wait);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int spi_sh_remove(struct platform_device *pdev)
> +{
> + struct spi_sh_data *ss = dev_get_drvdata(&pdev->dev);
> +
> + destroy_workqueue(ss->workqueue);
> + free_irq(ss->irq, ss);
> + iounmap(ss->addr);
> + spi_master_put(ss->master);
> +
> + return 0;
> +}
> +
> +static int spi_sh_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct spi_master *master;
> + struct spi_sh_data *ss;
> + int ret, irq;
> +
> + /* 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 spi_sh_data));
> + if (master = NULL) {
> + dev_err(&pdev->dev, "spi_alloc_master error.\n");
> + return -ENOMEM;
> + }
> +
> + ss = spi_master_get_devdata(master);
> + dev_set_drvdata(&pdev->dev, ss);
> +
> + ss->irq = irq;
> + ss->master = master;
> + ss->addr = ioremap(res->start, resource_size(res));
> + if (ss->addr = NULL) {
> + dev_err(&pdev->dev, "ioremap error.\n");
> + ret = -ENOMEM;
> + goto error1;
> + }
> + INIT_LIST_HEAD(&ss->queue);
> + spin_lock_init(&ss->lock);
> + INIT_WORK(&ss->ws, spi_sh_work);
> + init_waitqueue_head(&ss->wait);
> + ss->workqueue = create_singlethread_workqueue(
> + dev_name(master->dev.parent));
> + if (ss->workqueue = NULL) {
> + dev_err(&pdev->dev, "create workqueue error\n");
> + ret = -EBUSY;
> + goto error2;
> + }
> +
> + ret = request_irq(irq, spi_sh_irq, IRQF_DISABLED, "spi_sh", ss);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "request_irq error\n");
> + goto error3;
> + }
> +
> + master->num_chipselect = 2;
> + master->bus_num = pdev->id;
> + master->setup = spi_sh_setup;
> + master->transfer = spi_sh_transfer;
> + master->cleanup = spi_sh_cleanup;
> +
> + ret = spi_register_master(master);
> + if (ret < 0) {
> + printk(KERN_ERR "spi_register_master error.\n");
> + goto error4;
> + }
> +
> + printk(KERN_INFO "spi_sh: version %s\n", DRIVER_VERSION);
> +
> + return 0;
> +
> +error4:
> + free_irq(irq, ss);
> +error3:
> + destroy_workqueue(ss->workqueue);
> +error2:
> + iounmap(ss->addr);
> +error1:
> + spi_master_put(master);
> +
> + return ret;
> +}
> +
> +static struct platform_driver spi_sh_driver = {
> + .probe = spi_sh_probe,
> + .remove = spi_sh_remove,
> + .driver = {
> + .name = "sh_spi",
> + .owner = THIS_MODULE,
> + },
> +};
> +
> +static int __init spi_sh_init(void)
> +{
> + return platform_driver_register(&spi_sh_driver);
> +}
> +
> +static void __exit spi_sh_exit(void)
> +{
> + platform_driver_unregister(&spi_sh_driver);
> +}
> +module_init(spi_sh_init);
> +module_exit(spi_sh_exit);
> +
> +MODULE_DESCRIPTION("SH SPI bus driver");
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Yoshihiro Shimoda");
> +MODULE_ALIAS("platform:sh_spi");
> --
> 1.7.1