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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-sh-hspi.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-sh-hspi.c')
-rw-r--r--drivers/spi/spi-sh-hspi.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/spi/spi-sh-hspi.c b/drivers/spi/spi-sh-hspi.c
new file mode 100644
index 00000000000..934138c7b3d
--- /dev/null
+++ b/drivers/spi/spi-sh-hspi.c
@@ -0,0 +1,331 @@
+/*
+ * SuperH HSPI bus driver
+ *
+ * Copyright (C) 2011 Kuninori Morimoto
+ *
+ * Based on spi-sh.c:
+ * Based on pxa2xx_spi.c:
+ * Copyright (C) 2011 Renesas Solutions Corp.
+ * 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/clk.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/delay.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/io.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/sh_hspi.h>
+
+#define SPCR 0x00
+#define SPSR 0x04
+#define SPSCR 0x08
+#define SPTBR 0x0C
+#define SPRBR 0x10
+#define SPCR2 0x14
+
+/* SPSR */
+#define RXFL (1 << 2)
+
+#define hspi2info(h) (h->dev->platform_data)
+
+struct hspi_priv {
+ void __iomem *addr;
+ struct spi_master *master;
+ struct device *dev;
+ struct clk *clk;
+};
+
+/*
+ * basic function
+ */
+static void hspi_write(struct hspi_priv *hspi, int reg, u32 val)
+{
+ iowrite32(val, hspi->addr + reg);
+}
+
+static u32 hspi_read(struct hspi_priv *hspi, int reg)
+{
+ return ioread32(hspi->addr + reg);
+}
+
+/*
+ * transfer function
+ */
+static int hspi_status_check_timeout(struct hspi_priv *hspi, u32 mask, u32 val)
+{
+ int t = 256;
+
+ while (t--) {
+ if ((mask & hspi_read(hspi, SPSR)) == val)
+ return 0;
+
+ msleep(20);
+ }
+
+ dev_err(hspi->dev, "timeout\n");
+ return -ETIMEDOUT;
+}
+
+/*
+ * spi master function
+ */
+static int hspi_prepare_transfer(struct spi_master *master)
+{
+ struct hspi_priv *hspi = spi_master_get_devdata(master);
+
+ pm_runtime_get_sync(hspi->dev);
+ return 0;
+}
+
+static int hspi_unprepare_transfer(struct spi_master *master)
+{
+ struct hspi_priv *hspi = spi_master_get_devdata(master);
+
+ pm_runtime_put_sync(hspi->dev);
+ return 0;
+}
+
+static void hspi_hw_setup(struct hspi_priv *hspi,
+ struct spi_message *msg,
+ struct spi_transfer *t)
+{
+ struct spi_device *spi = msg->spi;
+ struct device *dev = hspi->dev;
+ u32 target_rate;
+ u32 spcr, idiv_clk;
+ u32 rate, best_rate, min, tmp;
+
+ target_rate = t ? t->speed_hz : 0;
+ if (!target_rate)
+ target_rate = spi->max_speed_hz;
+
+ /*
+ * find best IDIV/CLKCx settings
+ */
+ min = ~0;
+ best_rate = 0;
+ spcr = 0;
+ for (idiv_clk = 0x00; idiv_clk <= 0x3F; idiv_clk++) {
+ rate = clk_get_rate(hspi->clk);
+
+ /* IDIV calculation */
+ if (idiv_clk & (1 << 5))
+ rate /= 128;
+ else
+ rate /= 16;
+
+ /* CLKCx calculation */
+ rate /= (((idiv_clk & 0x1F) + 1) * 2) ;
+
+ /* save best settings */
+ tmp = abs(target_rate - rate);
+ if (tmp < min) {
+ min = tmp;
+ spcr = idiv_clk;
+ best_rate = rate;
+ }
+ }
+
+ if (spi->mode & SPI_CPHA)
+ spcr |= 1 << 7;
+ if (spi->mode & SPI_CPOL)
+ spcr |= 1 << 6;
+
+ dev_dbg(dev, "speed %d/%d\n", target_rate, best_rate);
+
+ hspi_write(hspi, SPCR, spcr);
+ hspi_write(hspi, SPSR, 0x0);
+ hspi_write(hspi, SPSCR, 0x1); /* master mode */
+}
+
+static int hspi_transfer_one_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct hspi_priv *hspi = spi_master_get_devdata(master);
+ struct spi_transfer *t;
+ u32 tx;
+ u32 rx;
+ int ret, i;
+
+ dev_dbg(hspi->dev, "%s\n", __func__);
+
+ ret = 0;
+ list_for_each_entry(t, &msg->transfers, transfer_list) {
+ hspi_hw_setup(hspi, msg, t);
+
+ for (i = 0; i < t->len; i++) {
+
+ /* wait remains */
+ ret = hspi_status_check_timeout(hspi, 0x1, 0);
+ if (ret < 0)
+ break;
+
+ tx = 0;
+ if (t->tx_buf)
+ tx = (u32)((u8 *)t->tx_buf)[i];
+
+ hspi_write(hspi, SPTBR, tx);
+
+ /* wait recive */
+ ret = hspi_status_check_timeout(hspi, 0x4, 0x4);
+ if (ret < 0)
+ break;
+
+ rx = hspi_read(hspi, SPRBR);
+ if (t->rx_buf)
+ ((u8 *)t->rx_buf)[i] = (u8)rx;
+
+ }
+
+ msg->actual_length += t->len;
+ }
+
+ msg->status = ret;
+ spi_finalize_current_message(master);
+
+ return ret;
+}
+
+static int hspi_setup(struct spi_device *spi)
+{
+ struct hspi_priv *hspi = spi_master_get_devdata(spi->master);
+ struct device *dev = hspi->dev;
+
+ if (8 != spi->bits_per_word) {
+ dev_err(dev, "bits_per_word should be 8\n");
+ return -EIO;
+ }
+
+ dev_dbg(dev, "%s setup\n", spi->modalias);
+
+ return 0;
+}
+
+static void hspi_cleanup(struct spi_device *spi)
+{
+ struct hspi_priv *hspi = spi_master_get_devdata(spi->master);
+ struct device *dev = hspi->dev;
+
+ dev_dbg(dev, "%s cleanup\n", spi->modalias);
+}
+
+static int __devinit hspi_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct spi_master *master;
+ struct hspi_priv *hspi;
+ struct clk *clk;
+ int ret;
+
+ /* get base addr */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "invalid resource\n");
+ return -EINVAL;
+ }
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*hspi));
+ if (!master) {
+ dev_err(&pdev->dev, "spi_alloc_master error.\n");
+ return -ENOMEM;
+ }
+
+ clk = clk_get(NULL, "shyway_clk");
+ if (!clk) {
+ dev_err(&pdev->dev, "shyway_clk is required\n");
+ ret = -EINVAL;
+ goto error0;
+ }
+
+ hspi = spi_master_get_devdata(master);
+ dev_set_drvdata(&pdev->dev, hspi);
+
+ /* init hspi */
+ hspi->master = master;
+ hspi->dev = &pdev->dev;
+ hspi->clk = clk;
+ hspi->addr = devm_ioremap(hspi->dev,
+ res->start, resource_size(res));
+ if (!hspi->addr) {
+ dev_err(&pdev->dev, "ioremap error.\n");
+ ret = -ENOMEM;
+ goto error1;
+ }
+
+ master->num_chipselect = 1;
+ master->bus_num = pdev->id;
+ master->setup = hspi_setup;
+ master->cleanup = hspi_cleanup;
+ master->mode_bits = SPI_CPOL | SPI_CPHA;
+ master->prepare_transfer_hardware = hspi_prepare_transfer;
+ master->transfer_one_message = hspi_transfer_one_message;
+ master->unprepare_transfer_hardware = hspi_unprepare_transfer;
+ ret = spi_register_master(master);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "spi_register_master error.\n");
+ goto error2;
+ }
+
+ pm_runtime_enable(&pdev->dev);
+
+ dev_info(&pdev->dev, "probed\n");
+
+ return 0;
+
+ error2:
+ devm_iounmap(hspi->dev, hspi->addr);
+ error1:
+ clk_put(clk);
+ error0:
+ spi_master_put(master);
+
+ return ret;
+}
+
+static int __devexit hspi_remove(struct platform_device *pdev)
+{
+ struct hspi_priv *hspi = dev_get_drvdata(&pdev->dev);
+
+ pm_runtime_disable(&pdev->dev);
+
+ clk_put(hspi->clk);
+ spi_unregister_master(hspi->master);
+ devm_iounmap(hspi->dev, hspi->addr);
+
+ return 0;
+}
+
+static struct platform_driver hspi_driver = {
+ .probe = hspi_probe,
+ .remove = __devexit_p(hspi_remove),
+ .driver = {
+ .name = "sh-hspi",
+ .owner = THIS_MODULE,
+ },
+};
+module_platform_driver(hspi_driver);
+
+MODULE_DESCRIPTION("SuperH HSPI bus driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
+MODULE_ALIAS("platform:sh_spi");