Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / mfd / stmpe-spi.c

diff --git a/kernel/drivers/mfd/stmpe-spi.c b/kernel/drivers/mfd/stmpe-spi.c
new file mode 100644 (file)
index 0000000..a81badb
--- /dev/null
+++ b/kernel/drivers/mfd/stmpe-spi.c
@@ -0,0 +1,149 @@
+/*
+ * ST Microelectronics MFD: stmpe's spi client specific driver
+ *
+ * Copyright (C) ST Microelectronics SA 2011
+ *
+ * License Terms: GNU General Public License, version 2
+ * Author: Viresh Kumar <viresh.linux@gmail.com> for ST Microelectronics
+ */
+
+#include <linux/spi/spi.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include "stmpe.h"
+
+#define READ_CMD       (1 << 7)
+
+static int spi_reg_read(struct stmpe *stmpe, u8 reg)
+{
+       struct spi_device *spi = stmpe->client;
+       int status = spi_w8r16(spi, reg | READ_CMD);
+
+       return (status < 0) ? status : status >> 8;
+}
+
+static int spi_reg_write(struct stmpe *stmpe, u8 reg, u8 val)
+{
+       struct spi_device *spi = stmpe->client;
+       u16 cmd = (val << 8) | reg;
+
+       return spi_write(spi, (const u8 *)&cmd, 2);
+}
+
+static int spi_block_read(struct stmpe *stmpe, u8 reg, u8 length, u8 *values)
+{
+       int ret, i;
+
+       for (i = 0; i < length; i++) {
+               ret = spi_reg_read(stmpe, reg + i);
+               if (ret < 0)
+                       return ret;
+               *(values + i) = ret;
+       }
+
+       return 0;
+}
+
+static int spi_block_write(struct stmpe *stmpe, u8 reg, u8 length,
+               const u8 *values)
+{
+       int ret = 0, i;
+
+       for (i = length; i > 0; i--, reg++) {
+               ret = spi_reg_write(stmpe, reg, *(values + i - 1));
+               if (ret < 0)
+                       return ret;
+       }
+
+       return ret;
+}
+
+static void spi_init(struct stmpe *stmpe)
+{
+       struct spi_device *spi = stmpe->client;
+
+       spi->bits_per_word = 8;
+
+       /* This register is only present for stmpe811 */
+       if (stmpe->variant->id_val == 0x0811)
+               spi_reg_write(stmpe, STMPE811_REG_SPI_CFG, spi->mode);
+
+       if (spi_setup(spi) < 0)
+               dev_dbg(&spi->dev, "spi_setup failed\n");
+}
+
+static struct stmpe_client_info spi_ci = {
+       .read_byte = spi_reg_read,
+       .write_byte = spi_reg_write,
+       .read_block = spi_block_read,
+       .write_block = spi_block_write,
+       .init = spi_init,
+};
+
+static int
+stmpe_spi_probe(struct spi_device *spi)
+{
+       const struct spi_device_id *id = spi_get_device_id(spi);
+
+       /* don't exceed max specified rate - 1MHz - Limitation of STMPE */
+       if (spi->max_speed_hz > 1000000) {
+               dev_dbg(&spi->dev, "f(sample) %d KHz?\n",
+                               (spi->max_speed_hz/1000));
+               return -EINVAL;
+       }
+
+       spi_ci.irq = spi->irq;
+       spi_ci.client = spi;
+       spi_ci.dev = &spi->dev;
+
+       return stmpe_probe(&spi_ci, id->driver_data);
+}
+
+static int stmpe_spi_remove(struct spi_device *spi)
+{
+       struct stmpe *stmpe = spi_get_drvdata(spi);
+
+       return stmpe_remove(stmpe);
+}
+
+static const struct spi_device_id stmpe_spi_id[] = {
+       { "stmpe610", STMPE610 },
+       { "stmpe801", STMPE801 },
+       { "stmpe811", STMPE811 },
+       { "stmpe1601", STMPE1601 },
+       { "stmpe2401", STMPE2401 },
+       { "stmpe2403", STMPE2403 },
+       { }
+};
+MODULE_DEVICE_TABLE(spi, stmpe_id);
+
+static struct spi_driver stmpe_spi_driver = {
+       .driver = {
+               .name   = "stmpe-spi",
+               .owner  = THIS_MODULE,
+#ifdef CONFIG_PM
+               .pm     = &stmpe_dev_pm_ops,
+#endif
+       },
+       .probe          = stmpe_spi_probe,
+       .remove         = stmpe_spi_remove,
+       .id_table       = stmpe_spi_id,
+};
+
+static int __init stmpe_init(void)
+{
+       return spi_register_driver(&stmpe_spi_driver);
+}
+subsys_initcall(stmpe_init);
+
+static void __exit stmpe_exit(void)
+{
+       spi_unregister_driver(&stmpe_spi_driver);
+}
+module_exit(stmpe_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("STMPE MFD SPI Interface Driver");
+MODULE_AUTHOR("Viresh Kumar <viresh.linux@gmail.com>");