--- /dev/null
+/*
+ * R-Car THS/TSC thermal sensor driver
+ *
+ * Copyright (C) 2012 Renesas Solutions Corp.
+ * Kuninori Morimoto <kuninori.morimoto.gx@renesas.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; 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.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/thermal.h>
+
+#define THSCR 0x2c
+#define THSSR 0x30
+
+/* THSCR */
+#define CPTAP 0xf
+
+/* THSSR */
+#define CTEMP 0x3f
+
+
+struct rcar_thermal_priv {
+ void __iomem *base;
+ struct device *dev;
+ spinlock_t lock;
+ u32 comp;
+};
+
+/*
+ * basic functions
+ */
+static u32 rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg)
+{
+ unsigned long flags;
+ u32 ret;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ ret = ioread32(priv->base + reg);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return ret;
+}
+
+#if 0 /* no user at this point */
+static void rcar_thermal_write(struct rcar_thermal_priv *priv,
+ u32 reg, u32 data)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ iowrite32(data, priv->base + reg);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+#endif
+
+static void rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg,
+ u32 mask, u32 data)
+{
+ unsigned long flags;
+ u32 val;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ val = ioread32(priv->base + reg);
+ val &= ~mask;
+ val |= (data & mask);
+ iowrite32(val, priv->base + reg);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+/*
+ * zone device functions
+ */
+static int rcar_thermal_get_temp(struct thermal_zone_device *zone,
+ unsigned long *temp)
+{
+ struct rcar_thermal_priv *priv = zone->devdata;
+ int val, min, max, tmp;
+
+ tmp = -200; /* default */
+ while (1) {
+ if (priv->comp < 1 || priv->comp > 12) {
+ dev_err(priv->dev,
+ "THSSR invalid data (%d)\n", priv->comp);
+ priv->comp = 4; /* for next thermal */
+ return -EINVAL;
+ }
+
+ /*
+ * THS comparator offset and the reference temperature
+ *
+ * Comparator | reference | Temperature field
+ * offset | temperature | measurement
+ * | (degrees C) | (degrees C)
+ * -------------+---------------+-------------------
+ * 1 | -45 | -45 to -30
+ * 2 | -30 | -30 to -15
+ * 3 | -15 | -15 to 0
+ * 4 | 0 | 0 to +15
+ * 5 | +15 | +15 to +30
+ * 6 | +30 | +30 to +45
+ * 7 | +45 | +45 to +60
+ * 8 | +60 | +60 to +75
+ * 9 | +75 | +75 to +90
+ * 10 | +90 | +90 to +105
+ * 11 | +105 | +105 to +120
+ * 12 | +120 | +120 to +135
+ */
+
+ /* calculate thermal limitation */
+ min = (priv->comp * 15) - 60;
+ max = min + 15;
+
+ /*
+ * we need to wait 300us after changing comparator offset
+ * to get stable temperature.
+ * see "Usage Notes" on datasheet
+ */
+ rcar_thermal_bset(priv, THSCR, CPTAP, priv->comp);
+ udelay(300);
+
+ /* calculate current temperature */
+ val = rcar_thermal_read(priv, THSSR) & CTEMP;
+ val = (val * 5) - 65;
+
+ dev_dbg(priv->dev, "comp/min/max/val = %d/%d/%d/%d\n",
+ priv->comp, min, max, val);
+
+ /*
+ * If val is same as min/max, then,
+ * it should try again on next comparator.
+ * But the val might be correct temperature.
+ * Keep it on "tmp" and compare with next val.
+ */
+ if (tmp == val)
+ break;
+
+ if (val <= min) {
+ tmp = min;
+ priv->comp--; /* try again */
+ } else if (val >= max) {
+ tmp = max;
+ priv->comp++; /* try again */
+ } else {
+ tmp = val;
+ break;
+ }
+ }
+
+ *temp = tmp;
+ return 0;
+}
+
+static struct thermal_zone_device_ops rcar_thermal_zone_ops = {
+ .get_temp = rcar_thermal_get_temp,
+};
+
+/*
+ * platform functions
+ */
+static int rcar_thermal_probe(struct platform_device *pdev)
+{
+ struct thermal_zone_device *zone;
+ struct rcar_thermal_priv *priv;
+ struct resource *res;
+ int ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "Could not get platform resource\n");
+ return -ENODEV;
+ }
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ dev_err(&pdev->dev, "Could not allocate priv\n");
+ return -ENOMEM;
+ }
+
+ priv->comp = 4; /* basic setup */
+ priv->dev = &pdev->dev;
+ spin_lock_init(&priv->lock);
+ priv->base = devm_ioremap_nocache(&pdev->dev,
+ res->start, resource_size(res));
+ if (!priv->base) {
+ dev_err(&pdev->dev, "Unable to ioremap thermal register\n");
+ ret = -ENOMEM;
+ goto error_free_priv;
+ }
+
+ zone = thermal_zone_device_register("rcar_thermal", 0, priv,
+ &rcar_thermal_zone_ops, 0, 0);
+ if (IS_ERR(zone)) {
+ dev_err(&pdev->dev, "thermal zone device is NULL\n");
+ ret = PTR_ERR(zone);
+ goto error_iounmap;
+ }
+
+ platform_set_drvdata(pdev, zone);
+
+ dev_info(&pdev->dev, "proved\n");
+
+ return 0;
+
+error_iounmap:
+ devm_iounmap(&pdev->dev, priv->base);
+error_free_priv:
+ devm_kfree(&pdev->dev, priv);
+
+ return ret;
+}
+
+static int rcar_thermal_remove(struct platform_device *pdev)
+{
+ struct thermal_zone_device *zone = platform_get_drvdata(pdev);
+ struct rcar_thermal_priv *priv = zone->devdata;
+
+ thermal_zone_device_unregister(zone);
+ platform_set_drvdata(pdev, NULL);
+
+ devm_iounmap(&pdev->dev, priv->base);
+ devm_kfree(&pdev->dev, priv);
+
+ return 0;
+}
+
+static struct platform_driver rcar_thermal_driver = {
+ .driver = {
+ .name = "rcar_thermal",
+ },
+ .probe = rcar_thermal_probe,
+ .remove = rcar_thermal_remove,
+};
+module_platform_driver(rcar_thermal_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver");
+MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
projects / openwrt / staging / blogic.git / commitdiff