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path: root/drivers/i2c/busses/i2c-at91.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-at91.c')
-rw-r--r--drivers/i2c/busses/i2c-at91.c130
1 files changed, 79 insertions, 51 deletions
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 917d54588d95..636fd2efad88 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -31,10 +31,13 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/platform_data/dma-atmel.h>
+#include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
#define DEFAULT_TWI_CLK_HZ 100000 /* max 400 Kbits/s */
#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */
#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */
+#define AUTOSUSPEND_TIMEOUT 2000
/* AT91 TWI register definitions */
#define AT91_TWI_CR 0x0000 /* Control Register */
@@ -72,7 +75,6 @@ struct at91_twi_pdata {
unsigned clk_max_div;
unsigned clk_offset;
bool has_unre_flag;
- bool has_dma_support;
struct at_dma_slave dma_slave;
};
@@ -434,7 +436,7 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
}
}
- ret = wait_for_completion_io_timeout(&dev->cmd_complete,
+ ret = wait_for_completion_timeout(&dev->cmd_complete,
dev->adapter.timeout);
if (ret == 0) {
dev_err(dev->dev, "controller timed out\n");
@@ -481,6 +483,10 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
dev_dbg(&adap->dev, "at91_xfer: processing %d messages:\n", num);
+ ret = pm_runtime_get_sync(dev->dev);
+ if (ret < 0)
+ goto out;
+
/*
* The hardware can handle at most two messages concatenated by a
* repeated start via it's internal address feature.
@@ -488,18 +494,21 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
if (num > 2) {
dev_err(dev->dev,
"cannot handle more than two concatenated messages.\n");
- return 0;
+ ret = 0;
+ goto out;
} else if (num == 2) {
int internal_address = 0;
int i;
if (msg->flags & I2C_M_RD) {
dev_err(dev->dev, "first transfer must be write.\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
if (msg->len > 3) {
dev_err(dev->dev, "first message size must be <= 3.\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
/* 1st msg is put into the internal address, start with 2nd */
@@ -523,7 +532,12 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
ret = at91_do_twi_transfer(dev);
- return (ret < 0) ? ret : num;
+ ret = (ret < 0) ? ret : num;
+out:
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+
+ return ret;
}
static u32 at91_twi_func(struct i2c_adapter *adapter)
@@ -541,35 +555,30 @@ static struct at91_twi_pdata at91rm9200_config = {
.clk_max_div = 5,
.clk_offset = 3,
.has_unre_flag = true,
- .has_dma_support = false,
};
static struct at91_twi_pdata at91sam9261_config = {
.clk_max_div = 5,
.clk_offset = 4,
.has_unre_flag = false,
- .has_dma_support = false,
};
static struct at91_twi_pdata at91sam9260_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
- .has_dma_support = false,
};
static struct at91_twi_pdata at91sam9g20_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
- .has_dma_support = false,
};
static struct at91_twi_pdata at91sam9g10_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
- .has_dma_support = false,
};
static const struct platform_device_id at91_twi_devtypes[] = {
@@ -598,7 +607,6 @@ static struct at91_twi_pdata at91sam9x5_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
- .has_dma_support = true,
};
static const struct of_device_id atmel_twi_dt_ids[] = {
@@ -627,30 +635,11 @@ static const struct of_device_id atmel_twi_dt_ids[] = {
MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
#endif
-static bool filter(struct dma_chan *chan, void *pdata)
-{
- struct at91_twi_pdata *sl_pdata = pdata;
- struct at_dma_slave *sl;
-
- if (!sl_pdata)
- return false;
-
- sl = &sl_pdata->dma_slave;
- if (sl && (sl->dma_dev == chan->device->dev)) {
- chan->private = sl;
- return true;
- } else {
- return false;
- }
-}
-
static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
{
int ret = 0;
- struct at91_twi_pdata *pdata = dev->pdata;
struct dma_slave_config slave_config;
struct at91_twi_dma *dma = &dev->dma;
- dma_cap_mask_t mask;
memset(&slave_config, 0, sizeof(slave_config));
slave_config.src_addr = (dma_addr_t)phy_addr + AT91_TWI_RHR;
@@ -661,22 +650,17 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
slave_config.dst_maxburst = 1;
slave_config.device_fc = false;
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
-
- dma->chan_tx = dma_request_slave_channel_compat(mask, filter, pdata,
- dev->dev, "tx");
- if (!dma->chan_tx) {
- dev_err(dev->dev, "can't get a DMA channel for tx\n");
- ret = -EBUSY;
+ dma->chan_tx = dma_request_slave_channel_reason(dev->dev, "tx");
+ if (IS_ERR(dma->chan_tx)) {
+ ret = PTR_ERR(dma->chan_tx);
+ dma->chan_tx = NULL;
goto error;
}
- dma->chan_rx = dma_request_slave_channel_compat(mask, filter, pdata,
- dev->dev, "rx");
- if (!dma->chan_rx) {
- dev_err(dev->dev, "can't get a DMA channel for rx\n");
- ret = -EBUSY;
+ dma->chan_rx = dma_request_slave_channel_reason(dev->dev, "rx");
+ if (IS_ERR(dma->chan_rx)) {
+ ret = PTR_ERR(dma->chan_rx);
+ dma->chan_rx = NULL;
goto error;
}
@@ -697,6 +681,7 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
sg_init_table(&dma->sg, 1);
dma->buf_mapped = false;
dma->xfer_in_progress = false;
+ dev->use_dma = true;
dev_info(dev->dev, "using %s (tx) and %s (rx) for DMA transfers\n",
dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
@@ -704,7 +689,8 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
return ret;
error:
- dev_info(dev->dev, "can't use DMA\n");
+ if (ret != -EPROBE_DEFER)
+ dev_info(dev->dev, "can't use DMA, error %d\n", ret);
if (dma->chan_rx)
dma_release_channel(dma->chan_rx);
if (dma->chan_tx)
@@ -772,9 +758,10 @@ static int at91_twi_probe(struct platform_device *pdev)
}
clk_prepare_enable(dev->clk);
- if (dev->pdata->has_dma_support) {
- if (at91_twi_configure_dma(dev, phy_addr) == 0)
- dev->use_dma = true;
+ if (dev->dev->of_node) {
+ rc = at91_twi_configure_dma(dev, phy_addr);
+ if (rc == -EPROBE_DEFER)
+ return rc;
}
rc = of_property_read_u32(dev->dev->of_node, "clock-frequency",
@@ -795,11 +782,20 @@ static int at91_twi_probe(struct platform_device *pdev)
dev->adapter.timeout = AT91_I2C_TIMEOUT;
dev->adapter.dev.of_node = pdev->dev.of_node;
+ pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT);
+ pm_runtime_use_autosuspend(dev->dev);
+ pm_runtime_set_active(dev->dev);
+ pm_runtime_enable(dev->dev);
+
rc = i2c_add_numbered_adapter(&dev->adapter);
if (rc) {
dev_err(dev->dev, "Adapter %s registration failed\n",
dev->adapter.name);
clk_disable_unprepare(dev->clk);
+
+ pm_runtime_disable(dev->dev);
+ pm_runtime_set_suspended(dev->dev);
+
return rc;
}
@@ -814,6 +810,9 @@ static int at91_twi_remove(struct platform_device *pdev)
i2c_del_adapter(&dev->adapter);
clk_disable_unprepare(dev->clk);
+ pm_runtime_disable(dev->dev);
+ pm_runtime_set_suspended(dev->dev);
+
return 0;
}
@@ -823,7 +822,9 @@ static int at91_twi_runtime_suspend(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
- clk_disable(twi_dev->clk);
+ clk_disable_unprepare(twi_dev->clk);
+
+ pinctrl_pm_select_sleep_state(dev);
return 0;
}
@@ -832,10 +833,38 @@ static int at91_twi_runtime_resume(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
- return clk_enable(twi_dev->clk);
+ pinctrl_pm_select_default_state(dev);
+
+ return clk_prepare_enable(twi_dev->clk);
+}
+
+static int at91_twi_suspend_noirq(struct device *dev)
+{
+ if (!pm_runtime_status_suspended(dev))
+ at91_twi_runtime_suspend(dev);
+
+ return 0;
+}
+
+static int at91_twi_resume_noirq(struct device *dev)
+{
+ int ret;
+
+ if (!pm_runtime_status_suspended(dev)) {
+ ret = at91_twi_runtime_resume(dev);
+ if (ret)
+ return ret;
+ }
+
+ pm_runtime_mark_last_busy(dev);
+ pm_request_autosuspend(dev);
+
+ return 0;
}
static const struct dev_pm_ops at91_twi_pm = {
+ .suspend_noirq = at91_twi_suspend_noirq,
+ .resume_noirq = at91_twi_resume_noirq,
.runtime_suspend = at91_twi_runtime_suspend,
.runtime_resume = at91_twi_runtime_resume,
};
@@ -851,7 +880,6 @@ static struct platform_driver at91_twi_driver = {
.id_table = at91_twi_devtypes,
.driver = {
.name = "at91_i2c",
- .owner = THIS_MODULE,
.of_match_table = of_match_ptr(atmel_twi_dt_ids),
.pm = at91_twi_pm_ops,
},
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.