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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.c100
1 files changed, 72 insertions, 28 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index bc8773333155..373dd4d47765 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -18,10 +18,6 @@
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
* ----------------------------------------------------------------------------
*
*/
@@ -30,6 +26,7 @@
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/clk.h>
+#include <linux/clk-provider.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/err.h>
@@ -41,6 +38,7 @@
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/acpi.h>
+#include <linux/platform_data/i2c-designware.h>
#include "i2c-designware-core.h"
static struct i2c_algorithm i2c_dw_algo = {
@@ -79,10 +77,7 @@ static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
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;
+ const struct acpi_device_id *id;
dev->adapter.nr = -1;
dev->tx_fifo_depth = 32;
@@ -92,14 +87,33 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev)
* 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, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, NULL);
dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt,
- fs_mode ? &dev->sda_hold_time : NULL);
+ &dev->sda_hold_time);
+
+ /*
+ * Provide a way for Designware I2C host controllers that are not
+ * based on Intel LPSS to specify their input clock frequency via
+ * id->driver_data.
+ */
+ id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
+ if (id && id->driver_data)
+ clk_register_fixed_rate(&pdev->dev, dev_name(&pdev->dev), NULL,
+ CLK_IS_ROOT, id->driver_data);
return 0;
}
+static void dw_i2c_acpi_unconfigure(struct platform_device *pdev)
+{
+ struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
+ const struct acpi_device_id *id;
+
+ id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
+ if (id && id->driver_data)
+ clk_unregister(dev->clk);
+}
+
static const struct acpi_device_id dw_i2c_acpi_match[] = {
{ "INT33C2", 0 },
{ "INT33C3", 0 },
@@ -107,6 +121,7 @@ static const struct acpi_device_id dw_i2c_acpi_match[] = {
{ "INT3433", 0 },
{ "80860F41", 0 },
{ "808622C1", 0 },
+ { "AMD0010", 133 * 1000 * 1000 },
{ }
};
MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
@@ -115,6 +130,7 @@ static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
{
return -ENODEV;
}
+static inline void dw_i2c_acpi_unconfigure(struct platform_device *pdev) { }
#endif
static int dw_i2c_probe(struct platform_device *pdev)
@@ -122,7 +138,9 @@ static int dw_i2c_probe(struct platform_device *pdev)
struct dw_i2c_dev *dev;
struct i2c_adapter *adap;
struct resource *mem;
+ struct dw_i2c_platform_data *pdata;
int irq, r;
+ u32 clk_freq, ht = 0;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
@@ -145,21 +163,14 @@ static int dw_i2c_probe(struct platform_device *pdev)
dev->irq = irq;
platform_set_drvdata(pdev, dev);
- dev->clk = devm_clk_get(&pdev->dev, NULL);
- dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
-
- if (IS_ERR(dev->clk))
- 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);
+ /* fast mode by default because of legacy reasons */
+ clk_freq = 400000;
+ if (ACPI_COMPANION(&pdev->dev)) {
+ dw_i2c_acpi_configure(pdev);
+ } else if (pdev->dev.of_node) {
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);
of_property_read_u32(pdev->dev.of_node,
"i2c-sda-falling-time-ns",
@@ -167,6 +178,21 @@ static int dw_i2c_probe(struct platform_device *pdev)
of_property_read_u32(pdev->dev.of_node,
"i2c-scl-falling-time-ns",
&dev->scl_falling_time);
+
+ of_property_read_u32(pdev->dev.of_node, "clock-frequency",
+ &clk_freq);
+
+ /* Only standard mode at 100kHz and fast mode at 400kHz
+ * are supported.
+ */
+ if (clk_freq != 100000 && clk_freq != 400000) {
+ dev_err(&pdev->dev, "Only 100kHz and 400kHz supported");
+ return -EINVAL;
+ }
+ } else {
+ pdata = dev_get_platdata(&pdev->dev);
+ if (pdata)
+ clk_freq = pdata->i2c_scl_freq;
}
dev->functionality =
@@ -176,12 +202,27 @@ static int dw_i2c_probe(struct platform_device *pdev)
I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_I2C_BLOCK;
- dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
- DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
+ if (clk_freq == 100000)
+ dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
+ DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_STD;
+ else
+ dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
+ DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
- /* Try first if we can configure the device from ACPI */
- r = dw_i2c_acpi_configure(pdev);
- if (r) {
+ dev->clk = devm_clk_get(&pdev->dev, NULL);
+ dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
+ if (IS_ERR(dev->clk))
+ return PTR_ERR(dev->clk);
+ clk_prepare_enable(dev->clk);
+
+ if (!dev->sda_hold_time && ht) {
+ u32 ic_clk = dev->get_clk_rate_khz(dev);
+
+ dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000,
+ 1000000);
+ }
+
+ if (!dev->tx_fifo_depth) {
u32 param1 = i2c_dw_read_comp_param(dev);
dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
@@ -237,6 +278,9 @@ static int dw_i2c_remove(struct platform_device *pdev)
pm_runtime_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
+ if (ACPI_COMPANION(&pdev->dev))
+ dw_i2c_acpi_unconfigure(pdev);
+
return 0;
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-29 04:16:38 +0300