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path: root/drivers/i2c/busses/i2c-designware-platdrv.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-designware-platdrv.c')
-rw-r--r--drivers/i2c/busses/i2c-designware-platdrv.c72
1 files changed, 57 insertions, 15 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 35b70a1..d0bdac0 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -34,7 +34,7 @@
#include <linux/sched.h>
#include <linux/err.h>
#include <linux/interrupt.h>
-#include <linux/of_i2c.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
@@ -53,9 +53,33 @@ static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
}
#ifdef CONFIG_ACPI
+static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
+ u16 *hcnt, u16 *lcnt, u32 *sda_hold)
+{
+ struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+ acpi_handle handle = ACPI_HANDLE(&pdev->dev);
+ union acpi_object *obj;
+
+ if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
+ return;
+
+ obj = (union acpi_object *)buf.pointer;
+ if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) {
+ const union acpi_object *objs = obj->package.elements;
+
+ *hcnt = (u16)objs[0].integer.value;
+ *lcnt = (u16)objs[1].integer.value;
+ if (sda_hold)
+ *sda_hold = (u32)objs[2].integer.value;
+ }
+
+ kfree(buf.pointer);
+}
+
static int dw_i2c_acpi_configure(struct platform_device *pdev)
{
struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
+ bool fs_mode = dev->master_cfg & DW_IC_CON_SPEED_FAST;
if (!ACPI_HANDLE(&pdev->dev))
return -ENODEV;
@@ -63,12 +87,24 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev)
dev->adapter.nr = -1;
dev->tx_fifo_depth = 32;
dev->rx_fifo_depth = 32;
+
+ /*
+ * Try to get SDA hold time and *CNT values from an ACPI method if
+ * it exists for both supported speed modes.
+ */
+ dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt,
+ fs_mode ? NULL : &dev->sda_hold_time);
+ dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt,
+ fs_mode ? &dev->sda_hold_time : NULL);
+
return 0;
}
static const struct acpi_device_id dw_i2c_acpi_match[] = {
{ "INT33C2", 0 },
{ "INT33C3", 0 },
+ { "INT3432", 0 },
+ { "INT3433", 0 },
{ "80860F41", 0 },
{ }
};
@@ -87,13 +123,6 @@ static int dw_i2c_probe(struct platform_device *pdev)
struct resource *mem;
int irq, r;
- /* NOTE: driver uses the static register mapping */
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!mem) {
- dev_err(&pdev->dev, "no mem resource?\n");
- return -EINVAL;
- }
-
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "no irq resource?\n");
@@ -104,6 +133,7 @@ static int dw_i2c_probe(struct platform_device *pdev)
if (!dev)
return -ENOMEM;
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
dev->base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(dev->base))
return PTR_ERR(dev->base);
@@ -121,6 +151,16 @@ static int dw_i2c_probe(struct platform_device *pdev)
return PTR_ERR(dev->clk);
clk_prepare_enable(dev->clk);
+ if (pdev->dev.of_node) {
+ u32 ht = 0;
+ u32 ic_clk = dev->get_clk_rate_khz(dev);
+
+ of_property_read_u32(pdev->dev.of_node,
+ "i2c-sda-hold-time-ns", &ht);
+ dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000,
+ 1000000);
+ }
+
dev->functionality =
I2C_FUNC_I2C |
I2C_FUNC_10BIT_ADDR |
@@ -167,8 +207,6 @@ static int dw_i2c_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "failure adding adapter\n");
return r;
}
- of_i2c_register_devices(adap);
- acpi_i2c_register_devices(adap);
pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
pm_runtime_use_autosuspend(&pdev->dev);
@@ -202,7 +240,7 @@ static const struct of_device_id dw_i2c_of_match[] = {
MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
#endif
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
static int dw_i2c_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
@@ -223,27 +261,31 @@ static int dw_i2c_resume(struct device *dev)
return 0;
}
-#endif
static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume);
+#define DW_I2C_DEV_PM_OPS (&dw_i2c_dev_pm_ops)
+#else
+#define DW_I2C_DEV_PM_OPS NULL
+#endif
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:i2c_designware");
static struct platform_driver dw_i2c_driver = {
- .remove = dw_i2c_remove,
+ .probe = dw_i2c_probe,
+ .remove = dw_i2c_remove,
.driver = {
.name = "i2c_designware",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(dw_i2c_of_match),
.acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
- .pm = &dw_i2c_dev_pm_ops,
+ .pm = DW_I2C_DEV_PM_OPS,
},
};
static int __init dw_i2c_init_driver(void)
{
- return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
+ return platform_driver_register(&dw_i2c_driver);
}
subsys_initcall(dw_i2c_init_driver);