i2c-designware: add support for Intel Lynxpoint
Intel Lynxpoint has two I2C controllers. These controllers are enumerated
from ACPI namespace with IDs INT33C2 and INT33C3. Add support for these to
the I2C DesignWare platform driver.
This is based on the work of Dirk Brandewie.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index d8afc85..d2a33e9 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -40,6 +40,7 @@
#include <linux/pm_runtime.h>
#include <linux/io.h>
#include <linux/slab.h>
+#include <linux/acpi.h>
#include "i2c-designware-core.h"
static struct i2c_algorithm i2c_dw_algo = {
@@ -51,6 +52,42 @@
return clk_get_rate(dev->clk)/1000;
}
+#ifdef CONFIG_ACPI
+static int dw_i2c_acpi_configure(struct platform_device *pdev)
+{
+ struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
+ struct acpi_device *adev;
+ int busno, ret;
+
+ if (!ACPI_HANDLE(&pdev->dev))
+ return -ENODEV;
+
+ ret = acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev);
+ if (ret)
+ return -ENODEV;
+
+ dev->adapter.nr = -1;
+ if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &busno))
+ dev->adapter.nr = busno;
+
+ dev->tx_fifo_depth = 32;
+ dev->rx_fifo_depth = 32;
+ return 0;
+}
+
+static const struct acpi_device_id dw_i2c_acpi_match[] = {
+ { "INT33C2", 0 },
+ { "INT33C3", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
+#else
+static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
+{
+ return -ENODEV;
+}
+#endif
+
static int dw_i2c_probe(struct platform_device *pdev)
{
struct dw_i2c_dev *dev;
@@ -115,18 +152,22 @@
r = -EBUSY;
goto err_unuse_clocks;
}
- {
+
+ /* Try first if we can configure the device from ACPI */
+ r = dw_i2c_acpi_configure(pdev);
+ if (r) {
u32 param1 = i2c_dw_read_comp_param(dev);
dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
+ dev->adapter.nr = pdev->id;
}
r = i2c_dw_init(dev);
if (r)
goto err_iounmap;
i2c_dw_disable_int(dev);
- r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev);
+ r = request_irq(dev->irq, i2c_dw_isr, IRQF_SHARED, pdev->name, dev);
if (r) {
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
goto err_iounmap;
@@ -141,14 +182,15 @@
adap->algo = &i2c_dw_algo;
adap->dev.parent = &pdev->dev;
adap->dev.of_node = pdev->dev.of_node;
+ ACPI_HANDLE_SET(&adap->dev, ACPI_HANDLE(&pdev->dev));
- adap->nr = pdev->id;
r = i2c_add_numbered_adapter(adap);
if (r) {
dev_err(&pdev->dev, "failure adding adapter\n");
goto err_free_irq;
}
of_i2c_register_devices(adap);
+ acpi_i2c_register_devices(adap);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
@@ -243,6 +285,7 @@
.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,
},
};