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Diffstat (limited to 'drivers/i2c/busses/i2c-ocores.c')
-rw-r--r--drivers/i2c/busses/i2c-ocores.c174
1 files changed, 132 insertions, 42 deletions
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index bffd5501ac2d..a873d0ad1acb 100644
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -4,15 +4,14 @@
*
* Peter Korsgaard <jacmet@sunsite.dk>
*
+ * Support for the GRLIB port of the controller by
+ * Andreas Larsson <andreas@gaisler.com>
+ *
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
-/*
- * This driver can be used from the device tree, see
- * Documentation/devicetree/bindings/i2c/ocore-i2c.txt
- */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
@@ -38,6 +37,8 @@ struct ocores_i2c {
int nmsgs;
int state; /* see STATE_ */
int clock_khz;
+ void (*setreg)(struct ocores_i2c *i2c, int reg, u8 value);
+ u8 (*getreg)(struct ocores_i2c *i2c, int reg);
};
/* registers */
@@ -71,24 +72,47 @@ struct ocores_i2c {
#define STATE_READ 3
#define STATE_ERROR 4
+#define TYPE_OCORES 0
+#define TYPE_GRLIB 1
+
+static void oc_setreg_8(struct ocores_i2c *i2c, int reg, u8 value)
+{
+ iowrite8(value, i2c->base + (reg << i2c->reg_shift));
+}
+
+static void oc_setreg_16(struct ocores_i2c *i2c, int reg, u8 value)
+{
+ iowrite16(value, i2c->base + (reg << i2c->reg_shift));
+}
+
+static void oc_setreg_32(struct ocores_i2c *i2c, int reg, u8 value)
+{
+ iowrite32(value, i2c->base + (reg << i2c->reg_shift));
+}
+
+static inline u8 oc_getreg_8(struct ocores_i2c *i2c, int reg)
+{
+ return ioread8(i2c->base + (reg << i2c->reg_shift));
+}
+
+static inline u8 oc_getreg_16(struct ocores_i2c *i2c, int reg)
+{
+ return ioread16(i2c->base + (reg << i2c->reg_shift));
+}
+
+static inline u8 oc_getreg_32(struct ocores_i2c *i2c, int reg)
+{
+ return ioread32(i2c->base + (reg << i2c->reg_shift));
+}
+
static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value)
{
- if (i2c->reg_io_width == 4)
- iowrite32(value, i2c->base + (reg << i2c->reg_shift));
- else if (i2c->reg_io_width == 2)
- iowrite16(value, i2c->base + (reg << i2c->reg_shift));
- else
- iowrite8(value, i2c->base + (reg << i2c->reg_shift));
+ i2c->setreg(i2c, reg, value);
}
static inline u8 oc_getreg(struct ocores_i2c *i2c, int reg)
{
- if (i2c->reg_io_width == 4)
- return ioread32(i2c->base + (reg << i2c->reg_shift));
- else if (i2c->reg_io_width == 2)
- return ioread16(i2c->base + (reg << i2c->reg_shift));
- else
- return ioread8(i2c->base + (reg << i2c->reg_shift));
+ return i2c->getreg(i2c, reg);
}
static void ocores_process(struct ocores_i2c *i2c)
@@ -227,11 +251,59 @@ static struct i2c_adapter ocores_adapter = {
.algo = &ocores_algorithm,
};
+static struct of_device_id ocores_i2c_match[] = {
+ {
+ .compatible = "opencores,i2c-ocores",
+ .data = (void *)TYPE_OCORES,
+ },
+ {
+ .compatible = "aeroflexgaisler,i2cmst",
+ .data = (void *)TYPE_GRLIB,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ocores_i2c_match);
+
#ifdef CONFIG_OF
+/* Read and write functions for the GRLIB port of the controller. Registers are
+ * 32-bit big endian and the PRELOW and PREHIGH registers are merged into one
+ * register. The subsequent registers has their offset decreased accordingly. */
+static u8 oc_getreg_grlib(struct ocores_i2c *i2c, int reg)
+{
+ u32 rd;
+ int rreg = reg;
+ if (reg != OCI2C_PRELOW)
+ rreg--;
+ rd = ioread32be(i2c->base + (rreg << i2c->reg_shift));
+ if (reg == OCI2C_PREHIGH)
+ return (u8)(rd >> 8);
+ else
+ return (u8)rd;
+}
+
+static void oc_setreg_grlib(struct ocores_i2c *i2c, int reg, u8 value)
+{
+ u32 curr, wr;
+ int rreg = reg;
+ if (reg != OCI2C_PRELOW)
+ rreg--;
+ if (reg == OCI2C_PRELOW || reg == OCI2C_PREHIGH) {
+ curr = ioread32be(i2c->base + (rreg << i2c->reg_shift));
+ if (reg == OCI2C_PRELOW)
+ wr = (curr & 0xff00) | value;
+ else
+ wr = (((u32)value) << 8) | (curr & 0xff);
+ } else {
+ wr = value;
+ }
+ iowrite32be(wr, i2c->base + (rreg << i2c->reg_shift));
+}
+
static int ocores_i2c_of_probe(struct platform_device *pdev,
struct ocores_i2c *i2c)
{
struct device_node *np = pdev->dev.of_node;
+ const struct of_device_id *match;
u32 val;
if (of_property_read_u32(np, "reg-shift", &i2c->reg_shift)) {
@@ -257,17 +329,26 @@ static int ocores_i2c_of_probe(struct platform_device *pdev,
of_property_read_u32(pdev->dev.of_node, "reg-io-width",
&i2c->reg_io_width);
+
+ match = of_match_node(ocores_i2c_match, pdev->dev.of_node);
+ if (match && (int)match->data == TYPE_GRLIB) {
+ dev_dbg(&pdev->dev, "GRLIB variant of i2c-ocores\n");
+ i2c->setreg = oc_setreg_grlib;
+ i2c->getreg = oc_getreg_grlib;
+ }
+
return 0;
}
#else
#define ocores_i2c_of_probe(pdev,i2c) -ENODEV
#endif
-static int __devinit ocores_i2c_probe(struct platform_device *pdev)
+static int ocores_i2c_probe(struct platform_device *pdev)
{
struct ocores_i2c *i2c;
struct ocores_i2c_platform_data *pdata;
- struct resource *res, *res2;
+ struct resource *res;
+ int irq;
int ret;
int i;
@@ -275,26 +356,17 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
if (!res)
return -ENODEV;
- res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
- if (!res2)
- return -ENODEV;
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
if (!i2c)
return -ENOMEM;
- if (!devm_request_mem_region(&pdev->dev, res->start,
- resource_size(res), pdev->name)) {
- dev_err(&pdev->dev, "Memory region busy\n");
- return -EBUSY;
- }
-
- i2c->base = devm_ioremap_nocache(&pdev->dev, res->start,
- resource_size(res));
- if (!i2c->base) {
- dev_err(&pdev->dev, "Unable to map registers\n");
- return -EIO;
- }
+ i2c->base = devm_request_and_ioremap(&pdev->dev, res);
+ if (!i2c->base)
+ return -EADDRNOTAVAIL;
pdata = pdev->dev.platform_data;
if (pdata) {
@@ -310,10 +382,34 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
if (i2c->reg_io_width == 0)
i2c->reg_io_width = 1; /* Set to default value */
+ if (!i2c->setreg || !i2c->getreg) {
+ switch (i2c->reg_io_width) {
+ case 1:
+ i2c->setreg = oc_setreg_8;
+ i2c->getreg = oc_getreg_8;
+ break;
+
+ case 2:
+ i2c->setreg = oc_setreg_16;
+ i2c->getreg = oc_getreg_16;
+ break;
+
+ case 4:
+ i2c->setreg = oc_setreg_32;
+ i2c->getreg = oc_getreg_32;
+ break;
+
+ default:
+ dev_err(&pdev->dev, "Unsupported I/O width (%d)\n",
+ i2c->reg_io_width);
+ return -EINVAL;
+ }
+ }
+
ocores_init(i2c);
init_waitqueue_head(&i2c->wait);
- ret = devm_request_irq(&pdev->dev, res2->start, ocores_isr, 0,
+ ret = devm_request_irq(&pdev->dev, irq, ocores_isr, 0,
pdev->name, i2c);
if (ret) {
dev_err(&pdev->dev, "Cannot claim IRQ\n");
@@ -345,7 +441,7 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
return 0;
}
-static int __devexit ocores_i2c_remove(struct platform_device *pdev)
+static int ocores_i2c_remove(struct platform_device *pdev)
{
struct ocores_i2c *i2c = platform_get_drvdata(pdev);
@@ -387,15 +483,9 @@ static SIMPLE_DEV_PM_OPS(ocores_i2c_pm, ocores_i2c_suspend, ocores_i2c_resume);
#define OCORES_I2C_PM NULL
#endif
-static struct of_device_id ocores_i2c_match[] = {
- { .compatible = "opencores,i2c-ocores", },
- {},
-};
-MODULE_DEVICE_TABLE(of, ocores_i2c_match);
-
static struct platform_driver ocores_i2c_driver = {
.probe = ocores_i2c_probe,
- .remove = __devexit_p(ocores_i2c_remove),
+ .remove = ocores_i2c_remove,
.driver = {
.owner = THIS_MODULE,
.name = "ocores-i2c",
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-16 03:39:09 +0300