path: root/recipes/linux/linux-2.6.27/ts72xx/0015-TS-72xx-MAX197-support.patch

From 7220a7235e7b6722fb7dc6e8f599a20bac224760 Mon Sep 17 00:00:00 2001
From: Matthieu Crapet <mcrapet@gmail.com>
Date: Sun, 4 Jan 2009 01:32:39 +0100
Subject: [PATCH] TS-72xx MAX197 support
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 arch/arm/mach-ep93xx/include/mach/ts72xx.h |    8 +
 arch/arm/mach-ep93xx/ts72xx.c              |   27 ++++
 drivers/misc/Kconfig                       |   21 +++
 drivers/misc/Makefile                      |    1 +
 drivers/misc/ts72xx_max197.c               |  235 ++++++++++++++++++++++++++++
 5 files changed, 292 insertions(+), 0 deletions(-)
 create mode 100644 drivers/misc/ts72xx_max197.c

diff --git a/arch/arm/mach-ep93xx/include/mach/ts72xx.h b/arch/arm/mach-ep93xx/include/mach/ts72xx.h
index bb67506..28372df 100644
--- a/arch/arm/mach-ep93xx/include/mach/ts72xx.h
+++ b/arch/arm/mach-ep93xx/include/mach/ts72xx.h
@@ -87,6 +87,14 @@
 #define TS72XX_WATCHDOG_FEED_PHYS_BASE	0x23c00000
 #define TS72XX_WATCHDOG_FEED_SIZE	0x00001000
 
+#define TS72XX_JUMPERS_MAX197_VIRT_BASE	0xfebf2000
+#define TS72XX_JUMPERS_MAX197_PHYS_BASE	0x10800000
+#define TS72XX_JUMPERS_MAX197_SIZE	0x00001000
+
+#define TS72XX_MAX197_SAMPLE_VIRT_BASE	0xfebf1000
+#define TS72XX_MAX197_SAMPLE_PHYS_BASE	0x10f00000
+#define TS72XX_MAX197_SAMPLE_SIZE	0x00001000
+
 #ifndef __ASSEMBLY__
 #include <asm/io.h>
 
diff --git a/arch/arm/mach-ep93xx/ts72xx.c b/arch/arm/mach-ep93xx/ts72xx.c
index a9d3939..ea3deeb 100644
--- a/arch/arm/mach-ep93xx/ts72xx.c
+++ b/arch/arm/mach-ep93xx/ts72xx.c
@@ -205,6 +205,29 @@ static struct platform_device ts72xx_watchdog_device = {
 	.resource = ts72xx_watchdog_resources,
 };
 
+static struct resource ts72xx_max197_resources[] = {
+	[0] = { /* sample/control register */
+		.start = TS72XX_MAX197_SAMPLE_PHYS_BASE,
+		.end   = TS72XX_MAX197_SAMPLE_PHYS_BASE + TS72XX_MAX197_SAMPLE_SIZE - 1,
+		.flags = IORESOURCE_MEM,
+	},
+	[1] = { /* busy bit */
+		.start = TS72XX_JUMPERS_MAX197_PHYS_BASE,
+		.end   = TS72XX_JUMPERS_MAX197_PHYS_BASE + TS72XX_JUMPERS_MAX197_SIZE - 1,
+		.flags = IORESOURCE_MEM,
+	},
+};
+
+static struct platform_device ts72xx_max197_device = {
+	.name = "ts72xx-max197",
+	.id   = -1,
+	.dev  = {
+		.platform_data  = NULL,
+	},
+	.num_resources  = ARRAY_SIZE(ts72xx_max197_resources),
+	.resource = ts72xx_max197_resources,
+};
+
 static void __init ts72xx_init_machine(void)
 {
 	ep93xx_init_devices();
@@ -220,6 +243,10 @@ static void __init ts72xx_init_machine(void)
 		(void *)(EP93XX_ETHERNET_BASE + 0x50), 6);
 	platform_device_register(&ts72xx_eth_device);
 	platform_device_register(&ts72xx_watchdog_device);
+
+	if (is_max197_installed()) {
+		platform_device_register(&ts72xx_max197_device);
+	}
 }
 
 MACHINE_START(TS72XX, "Technologic Systems TS-72xx SBC")
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index a726f3b..4c696c6 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -475,4 +475,25 @@ config SGI_GRU_DEBUG
 	This option enables addition debugging code for the SGI GRU driver. If
 	you are unsure, say N.
 
+config TS72XX_MAX197
+	tristate "TS-72xx MAX197 support"
+	depends on ARCH_EP93XX && MACH_TS72XX && SYSFS
+	help
+	  Say Y here if to include support for the MAX197 A/D converter
+	  optionally included on Technologic Systems SBCs.
+	  Default acquisition range is [0..5V].
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ts72xx_max197.
+
+if TS72XX_MAX197
+
+config TS72XX_MAX197_AVERAGE
+	bool "Average measurement"
+	help
+	  Say Y here to enable making average measurement. Default is 1.
+	  See /sys/module/ts72xx_max197/parameters/average file.
+
+endif # TS72XX_MAX197
+
 endif # MISC_DEVICES
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index c6c13f6..d97326f 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -30,3 +30,4 @@ obj-$(CONFIG_KGDB_TESTS)	+= kgdbts.o
 obj-$(CONFIG_SGI_XP)		+= sgi-xp/
 obj-$(CONFIG_SGI_GRU)		+= sgi-gru/
 obj-$(CONFIG_HP_ILO)		+= hpilo.o
+obj-$(CONFIG_TS72XX_MAX197)	+= ts72xx_max197.o
diff --git a/drivers/misc/ts72xx_max197.c b/drivers/misc/ts72xx_max197.c
new file mode 100644
index 0000000..f989de6
--- /dev/null
+++ b/drivers/misc/ts72xx_max197.c
@@ -0,0 +1,235 @@
+/*
+ *  TS-72XX max197 driver for Technologic Systems boards.
+ *
+ * Voltage conversion is taken from adc_logger from Jim Jackson.
+ * (c) Copyright 2008  Matthieu Crapet <mcrapet@gmail.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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <asm/io.h>
+
+#define DRV_VERSION "0.2"
+#define PFX "ts72xx_max197: "
+
+#define MAX197_RANGE_5_5   1 // [- 5V + 5V]
+#define MAX197_RANGE_10_10 3 // [-10V +10V]
+#define MAX197_RANGE_0_5   0 // [  0V + 5V]
+#define MAX197_RANGE_0_10  2 // [  0V +10V]
+
+#define MAX197_RESET_CHANNEL_CONF(x)       (~(3 << (2*(x))))
+#define MAX197_SET_CHANNEL_CONF(x, range)  ((range) << (2*(x)))
+#define MAX197_GET_CHANNEL_CONF(x, conf)   (((conf) >> (2*(x))) & 3)
+
+struct max197_config
+{
+  void __iomem *control_and_data_register;
+  void __iomem *busy_bit_register;
+  unsigned int channels; // two bits per channels
+};
+
+static struct max197_config conf;
+#ifdef CONFIG_TS72XX_MAX197_AVERAGE
+static ushort average = 1;
+#endif
+
+static ssize_t max197_acquire(struct device *dev,
+    struct device_attribute *attr, char *buf)
+{
+  int range, n;
+  signed short val;
+#ifdef CONFIG_TS72XX_MAX197_AVERAGE
+  int i, total;
+#endif
+
+  n = attr->attr.name[2] - 0x31;
+  range = MAX197_GET_CHANNEL_CONF(n, conf.channels);
+
+#ifdef CONFIG_TS72XX_MAX197_AVERAGE
+  val = 0; total = 0;
+  for (i = 0; i < average; i++) {
+#endif
+
+    __raw_writeb(((range << 3) | n | 0x40) & 0xFF,
+      conf.control_and_data_register);
+    while (__raw_readb(conf.busy_bit_register) & 0x80);
+    val = __raw_readw(conf.control_and_data_register);
+
+    //printk(PFX "%hd/%hd: 0x%04X\n", i+1, average, val);
+
+#ifdef CONFIG_TS72XX_MAX197_AVERAGE
+    total += val;
+  }
+  total /= average;
+  val = (signed short)total;
+#endif
+
+  /* We want three digit precision */
+  switch (range) {
+    case MAX197_RANGE_0_5:
+      val = ((val * 50000/4096)+5)/10;
+      break;
+    case MAX197_RANGE_5_5:
+    case MAX197_RANGE_0_10:
+      val = ((val * 100000/4096)+5)/10;
+      break;
+    case MAX197_RANGE_10_10:
+      val = ((val * 200000/4096)+5)/10;
+      break;
+  }
+
+  return sprintf(buf, "%d.%03d\n", val/1000, abs(val%1000));
+}
+
+static ssize_t max197_configure(struct device *dev,
+    struct device_attribute *attr, const char *buf, size_t len)
+{
+  int n = attr->attr.name[2] - 0x31;
+
+  long val = simple_strtol(buf, NULL, 10);
+  switch (val) {
+    case 10:
+      conf.channels &= MAX197_RESET_CHANNEL_CONF(n);
+      conf.channels |= MAX197_SET_CHANNEL_CONF(n, MAX197_RANGE_0_10);
+      break;
+    case 5:
+      conf.channels &= MAX197_RESET_CHANNEL_CONF(n);
+      conf.channels |= MAX197_SET_CHANNEL_CONF(n, MAX197_RANGE_0_5);
+      break;
+    case -10:
+      conf.channels &= MAX197_RESET_CHANNEL_CONF(n);
+      conf.channels |= MAX197_SET_CHANNEL_CONF(n, MAX197_RANGE_10_10);
+      break;
+    case -5:
+      conf.channels &= MAX197_RESET_CHANNEL_CONF(n);
+      conf.channels |= MAX197_SET_CHANNEL_CONF(n, MAX197_RANGE_5_5);
+      break;
+
+    default:
+      return -EINVAL;
+  }
+
+  return len;
+}
+
+static DEVICE_ATTR(ch1, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+static DEVICE_ATTR(ch2, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+static DEVICE_ATTR(ch3, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+static DEVICE_ATTR(ch4, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+static DEVICE_ATTR(ch5, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+static DEVICE_ATTR(ch6, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+static DEVICE_ATTR(ch7, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+static DEVICE_ATTR(ch8, S_IWUSR | S_IRUGO, max197_acquire, max197_configure);
+
+static struct attribute *max197_attributes[] = {
+  &dev_attr_ch1.attr,
+  &dev_attr_ch2.attr,
+  &dev_attr_ch3.attr,
+  &dev_attr_ch4.attr,
+  &dev_attr_ch5.attr,
+  &dev_attr_ch6.attr,
+  &dev_attr_ch7.attr,
+  &dev_attr_ch8.attr,
+  NULL
+};
+
+static struct attribute_group max197_group = {
+  .attrs = max197_attributes,
+  //.name = "channels",
+};
+
+static __devinit int ts72xx_max197_probe(struct platform_device *pdev)
+{
+  int err = 0;
+  struct resource *r_data, *r_busy;
+
+  r_data = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+  r_busy = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+
+  if (!r_data || !r_busy) {
+    dev_err(&pdev->dev, "missing resource(s)\n");
+    return -EINVAL;
+  }
+
+  conf.control_and_data_register = ioremap(r_data->start, r_data->end - r_data->start + 1);
+  if (!conf.control_and_data_register) {
+    err = -ENODEV;
+    goto exit;
+  }
+
+  conf.busy_bit_register = ioremap(r_busy->start, r_busy->end - r_busy->start + 1);
+  if (!conf.busy_bit_register) {
+    err = -ENODEV;
+    goto exit_unmap1;
+  }
+
+  conf.channels =
+    MAX197_SET_CHANNEL_CONF(0, MAX197_RANGE_0_5) |
+    MAX197_SET_CHANNEL_CONF(1, MAX197_RANGE_0_5) |
+    MAX197_SET_CHANNEL_CONF(2, MAX197_RANGE_0_5) |
+    MAX197_SET_CHANNEL_CONF(3, MAX197_RANGE_0_5) |
+    MAX197_SET_CHANNEL_CONF(4, MAX197_RANGE_0_5) |
+    MAX197_SET_CHANNEL_CONF(5, MAX197_RANGE_0_5) |
+    MAX197_SET_CHANNEL_CONF(6, MAX197_RANGE_0_5) |
+    MAX197_SET_CHANNEL_CONF(7, MAX197_RANGE_0_5);
+
+  /* Register sysfs hooks */
+  if ((err = sysfs_create_group(&pdev->dev.kobj, &max197_group)))
+    goto exit_unmap2;
+
+  printk(PFX  "TS-72xx max197 driver, v%s\n", DRV_VERSION);
+  return 0;
+
+exit_unmap2:
+  iounmap(conf.busy_bit_register);
+exit_unmap1:
+  iounmap(conf.control_and_data_register);
+exit:
+  return err;
+}
+
+static int __devexit ts72xx_max197_remove(struct platform_device *pdev)
+{
+  sysfs_remove_group(&pdev->dev.kobj, &max197_group);
+  iounmap(conf.busy_bit_register);
+  iounmap(conf.control_and_data_register);
+  return 0;
+}
+
+static struct platform_driver ts72xx_max197_platform_driver = {
+  .probe    = ts72xx_max197_probe,
+  .remove   = __devexit_p(ts72xx_max197_remove),
+  .driver = {
+    .name   = "ts72xx-max197",
+    .owner  = THIS_MODULE,
+  },
+};
+
+static int __init ts72xx_max197_init(void)
+{
+  return platform_driver_register(&ts72xx_max197_platform_driver);
+}
+
+static void __exit ts72xx_max197_exit(void)
+{
+  platform_driver_unregister(&ts72xx_max197_platform_driver);
+}
+
+#ifdef CONFIG_TS72XX_MAX197_AVERAGE
+module_param(average, ushort, S_IWUSR | S_IRUGO);
+MODULE_PARM_DESC(average, "Allow average measurement (default=1)");
+#endif
+
+MODULE_AUTHOR("Matthieu Crapet <mcrapet@gmail.com>");
+MODULE_DESCRIPTION("TS-72xx max197 driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
+
+module_init(ts72xx_max197_init);
+module_exit(ts72xx_max197_exit);
-- 
1.6.0.4