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Input: ad714x - use DMA-safe buffers for spi_write()
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spi_write() requires use of DMA-safe (cacheline aligned) buffers.
Also use the same buffers when reading data since to avoid extra
locking and potential memory allocation in spi_write_then_read().

Acked-by: Michael Hennerich <[email protected]>
Signed-off-by: Dmitry Torokhov <[email protected]>
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@dtor
dtor committed Aug 22, 2011
1 parent 6337de2 commit c0409fe
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Showing 4 changed files with 131 additions and 103 deletions.
60 changes: 33 additions & 27 deletions drivers/input/misc/ad714x-i2c.c
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Original file line number Diff line number Diff line change
Expand Up @@ -27,40 +27,46 @@ static int ad714x_i2c_resume(struct device *dev)

static SIMPLE_DEV_PM_OPS(ad714x_i2c_pm, ad714x_i2c_suspend, ad714x_i2c_resume);

static int ad714x_i2c_write(struct device *dev, unsigned short reg,
unsigned short data)
static int ad714x_i2c_write(struct ad714x_chip *chip,
unsigned short reg, unsigned short data)
{
struct i2c_client *client = to_i2c_client(dev);
int ret = 0;
unsigned short tx[2] = {
cpu_to_be16(reg),
cpu_to_be16(data)
};

ret = i2c_master_send(client, (u8 *)tx, 4);
if (ret < 0)
dev_err(&client->dev, "I2C write error\n");

return ret;
struct i2c_client *client = to_i2c_client(chip->dev);
int error;

chip->xfer_buf[0] = cpu_to_be16(reg);
chip->xfer_buf[1] = cpu_to_be16(data);

error = i2c_master_send(client, (u8 *)chip->xfer_buf,
2 * sizeof(*chip->xfer_buf));
if (unlikely(error < 0)) {
dev_err(&client->dev, "I2C write error: %d\n", error);
return error;
}

return 0;
}

static int ad714x_i2c_read(struct device *dev, unsigned short reg,
unsigned short *data)
static int ad714x_i2c_read(struct ad714x_chip *chip,
unsigned short reg, unsigned short *data)
{
struct i2c_client *client = to_i2c_client(dev);
int ret = 0;
unsigned short tx = cpu_to_be16(reg);
struct i2c_client *client = to_i2c_client(chip->dev);
int error;

chip->xfer_buf[0] = cpu_to_be16(reg);

ret = i2c_master_send(client, (u8 *)&tx, 2);
if (ret >= 0)
ret = i2c_master_recv(client, (u8 *)data, 2);
error = i2c_master_send(client, (u8 *)chip->xfer_buf,
sizeof(*chip->xfer_buf));
if (error >= 0)
error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
sizeof(*chip->xfer_buf));

if (unlikely(ret < 0))
dev_err(&client->dev, "I2C read error\n");
else
*data = be16_to_cpu(*data);
if (unlikely(error < 0)) {
dev_err(&client->dev, "I2C read error: %d\n", error);
return error;
}

return ret;
*data = be16_to_cpup(chip->xfer_buf);
return 0;
}

static int __devinit ad714x_i2c_probe(struct i2c_client *client,
Expand Down
51 changes: 37 additions & 14 deletions drivers/input/misc/ad714x-spi.c
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Original file line number Diff line number Diff line change
Expand Up @@ -30,31 +30,54 @@ static int ad714x_spi_resume(struct device *dev)

static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);

static int ad714x_spi_read(struct device *dev,
static int ad714x_spi_read(struct ad714x_chip *chip,
unsigned short reg, unsigned short *data)
{
struct spi_device *spi = to_spi_device(dev);
unsigned short tx = cpu_to_be16(AD714x_SPI_CMD_PREFIX |
struct spi_device *spi = to_spi_device(chip->dev);
struct spi_message message;
struct spi_transfer xfer[2];
int error;

spi_message_init(&message);
memset(xfer, 0, sizeof(xfer));

chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX |
AD714x_SPI_READ | reg);
int ret;
xfer[0].tx_buf = &chip->xfer_buf[0];
xfer[0].len = sizeof(chip->xfer_buf[0]);
spi_message_add_tail(&xfer[0], &message);

ret = spi_write_then_read(spi, &tx, 2, data, 2);
xfer[1].rx_buf = &chip->xfer_buf[1];
xfer[1].len = sizeof(chip->xfer_buf[1]);
spi_message_add_tail(&xfer[1], &message);

*data = be16_to_cpup(data);
error = spi_sync(spi, &message);
if (unlikely(error)) {
dev_err(chip->dev, "SPI read error: %d\n", error);
return error;
}

return ret;
*data = be16_to_cpu(chip->xfer_buf[1]);
return 0;
}

static int ad714x_spi_write(struct device *dev,
static int ad714x_spi_write(struct ad714x_chip *chip,
unsigned short reg, unsigned short data)
{
struct spi_device *spi = to_spi_device(dev);
unsigned short tx[2] = {
cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg),
cpu_to_be16(data)
};
struct spi_device *spi = to_spi_device(chip->dev);
int error;

return spi_write(spi, (u8 *)tx, 4);
chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg);
chip->xfer_buf[1] = cpu_to_be16(data);

error = spi_write(spi, (u8 *)chip->xfer_buf,
2 * sizeof(*chip->xfer_buf));
if (unlikely(error)) {
dev_err(chip->dev, "SPI write error: %d\n", error);
return error;
}

return 0;
}

static int __devinit ad714x_spi_probe(struct spi_device *spi)
Expand Down
90 changes: 30 additions & 60 deletions drivers/input/misc/ad714x.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -59,7 +59,6 @@
#define STAGE11_AMBIENT 0x27D

#define PER_STAGE_REG_NUM 36
#define STAGE_NUM 12
#define STAGE_CFGREG_NUM 8
#define SYS_CFGREG_NUM 8

Expand Down Expand Up @@ -124,28 +123,6 @@ struct ad714x_driver_data {
* information to integrate all things which will be private data
* of spi/i2c device
*/
struct ad714x_chip {
unsigned short h_state;
unsigned short l_state;
unsigned short c_state;
unsigned short adc_reg[STAGE_NUM];
unsigned short amb_reg[STAGE_NUM];
unsigned short sensor_val[STAGE_NUM];

struct ad714x_platform_data *hw;
struct ad714x_driver_data *sw;

int irq;
struct device *dev;
ad714x_read_t read;
ad714x_write_t write;

struct mutex mutex;

unsigned product;
unsigned version;
};

static void ad714x_use_com_int(struct ad714x_chip *ad714x,
int start_stage, int end_stage)
{
Expand All @@ -154,13 +131,13 @@ static void ad714x_use_com_int(struct ad714x_chip *ad714x,

mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);

ad714x->read(ad714x->dev, STG_COM_INT_EN_REG, &data);
ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
data |= 1 << end_stage;
ad714x->write(ad714x->dev, STG_COM_INT_EN_REG, data);
ad714x->write(ad714x, STG_COM_INT_EN_REG, data);

ad714x->read(ad714x->dev, STG_HIGH_INT_EN_REG, &data);
ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
data &= ~mask;
ad714x->write(ad714x->dev, STG_HIGH_INT_EN_REG, data);
ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
}

static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
Expand All @@ -171,13 +148,13 @@ static void ad714x_use_thr_int(struct ad714x_chip *ad714x,

mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);

ad714x->read(ad714x->dev, STG_COM_INT_EN_REG, &data);
ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
data &= ~(1 << end_stage);
ad714x->write(ad714x->dev, STG_COM_INT_EN_REG, data);
ad714x->write(ad714x, STG_COM_INT_EN_REG, data);

ad714x->read(ad714x->dev, STG_HIGH_INT_EN_REG, &data);
ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
data |= mask;
ad714x->write(ad714x->dev, STG_HIGH_INT_EN_REG, data);
ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
}

static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
Expand Down Expand Up @@ -274,10 +251,8 @@ static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
int i;

for (i = hw->start_stage; i <= hw->end_stage; i++) {
ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
&ad714x->adc_reg[i]);
ad714x->read(ad714x->dev,
STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
&ad714x->amb_reg[i]);

ad714x->sensor_val[i] = abs(ad714x->adc_reg[i] -
Expand Down Expand Up @@ -445,10 +420,8 @@ static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
int i;

for (i = hw->start_stage; i <= hw->end_stage; i++) {
ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
&ad714x->adc_reg[i]);
ad714x->read(ad714x->dev,
STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
&ad714x->amb_reg[i]);
if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
ad714x->sensor_val[i] = ad714x->adc_reg[i] -
Expand Down Expand Up @@ -598,10 +571,8 @@ static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
int i;

for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
&ad714x->adc_reg[i]);
ad714x->read(ad714x->dev,
STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
&ad714x->amb_reg[i]);
if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
ad714x->sensor_val[i] = ad714x->adc_reg[i] -
Expand Down Expand Up @@ -891,7 +862,7 @@ static int ad714x_hw_detect(struct ad714x_chip *ad714x)
{
unsigned short data;

ad714x->read(ad714x->dev, AD714X_PARTID_REG, &data);
ad714x->read(ad714x, AD714X_PARTID_REG, &data);
switch (data & 0xFFF0) {
case AD7142_PARTID:
ad714x->product = 0x7142;
Expand Down Expand Up @@ -940,23 +911,22 @@ static void ad714x_hw_init(struct ad714x_chip *ad714x)
for (i = 0; i < STAGE_NUM; i++) {
reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
for (j = 0; j < STAGE_CFGREG_NUM; j++)
ad714x->write(ad714x->dev, reg_base + j,
ad714x->write(ad714x, reg_base + j,
ad714x->hw->stage_cfg_reg[i][j]);
}

for (i = 0; i < SYS_CFGREG_NUM; i++)
ad714x->write(ad714x->dev, AD714X_SYSCFG_REG + i,
ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
ad714x->hw->sys_cfg_reg[i]);
for (i = 0; i < SYS_CFGREG_NUM; i++)
ad714x->read(ad714x->dev, AD714X_SYSCFG_REG + i,
&data);
ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data);

ad714x->write(ad714x->dev, AD714X_STG_CAL_EN_REG, 0xFFF);
ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);

/* clear all interrupts */
ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG, &data);
ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG, &data);
ad714x->read(ad714x->dev, STG_COM_INT_STA_REG, &data);
ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);
}

static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
Expand All @@ -966,9 +936,9 @@ static irqreturn_t ad714x_interrupt_thread(int irq, void *data)

mutex_lock(&ad714x->mutex);

ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG, &ad714x->l_state);
ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG, &ad714x->h_state);
ad714x->read(ad714x->dev, STG_COM_INT_STA_REG, &ad714x->c_state);
ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state);
ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &ad714x->h_state);
ad714x->read(ad714x, STG_COM_INT_STA_REG, &ad714x->c_state);

for (i = 0; i < ad714x->hw->button_num; i++)
ad714x_button_state_machine(ad714x, i);
Expand Down Expand Up @@ -1245,7 +1215,7 @@ int ad714x_disable(struct ad714x_chip *ad714x)
mutex_lock(&ad714x->mutex);

data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
ad714x->write(ad714x->dev, AD714X_PWR_CTRL, data);
ad714x->write(ad714x, AD714X_PWR_CTRL, data);

mutex_unlock(&ad714x->mutex);

Expand All @@ -1263,16 +1233,16 @@ int ad714x_enable(struct ad714x_chip *ad714x)

/* resume to non-shutdown mode */

ad714x->write(ad714x->dev, AD714X_PWR_CTRL,
ad714x->write(ad714x, AD714X_PWR_CTRL,
ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);

/* make sure the interrupt output line is not low level after resume,
* otherwise we will get no chance to enter falling-edge irq again
*/

ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG, &data);
ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG, &data);
ad714x->read(ad714x->dev, STG_COM_INT_STA_REG, &data);
ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);

mutex_unlock(&ad714x->mutex);

Expand Down
33 changes: 31 additions & 2 deletions drivers/input/misc/ad714x.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -11,11 +11,40 @@

#include <linux/types.h>

#define STAGE_NUM 12

struct device;
struct ad714x_platform_data;
struct ad714x_driver_data;
struct ad714x_chip;

typedef int (*ad714x_read_t)(struct device *, unsigned short, unsigned short *);
typedef int (*ad714x_write_t)(struct device *, unsigned short, unsigned short);
typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *);
typedef int (*ad714x_write_t)(struct ad714x_chip *, unsigned short, unsigned short);

struct ad714x_chip {
unsigned short h_state;
unsigned short l_state;
unsigned short c_state;
unsigned short adc_reg[STAGE_NUM];
unsigned short amb_reg[STAGE_NUM];
unsigned short sensor_val[STAGE_NUM];

struct ad714x_platform_data *hw;
struct ad714x_driver_data *sw;

int irq;
struct device *dev;
ad714x_read_t read;
ad714x_write_t write;

struct mutex mutex;

unsigned product;
unsigned version;

__be16 xfer_buf[16] ____cacheline_aligned;

};

int ad714x_disable(struct ad714x_chip *ad714x);
int ad714x_enable(struct ad714x_chip *ad714x);
Expand Down

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