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Input: atmel_tsadcc - use platform parameters
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Add a number of plafrom dependent parameters to atmel_tsadcc.  The
touchscreeen driver can now take into account the slight differences
that exist between IPs included in diferent products.  This will also
allow to adapt its behaivior to the caracteristics of the resistive
panel used.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
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Nicolas Ferre authored and Dmitry Torokhov committed Nov 20, 2009
1 parent ab9122c commit 970435a
Showing 1 changed file with 35 additions and 6 deletions.
41 changes: 35 additions & 6 deletions drivers/input/touchscreen/atmel_tsadcc.c
Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,8 @@
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <mach/board.h>
#include <mach/cpu.h>

/* Register definitions based on AT91SAM9RL64 preliminary draft datasheet */

Expand All @@ -36,7 +38,9 @@
#define ATMEL_TSADCC_LOWRES (1 << 4) /* Resolution selection */
#define ATMEL_TSADCC_SLEEP (1 << 5) /* Sleep mode */
#define ATMEL_TSADCC_PENDET (1 << 6) /* Pen Detect selection */
#define ATMEL_TSADCC_PRES (1 << 7) /* Pressure Measurement Selection */
#define ATMEL_TSADCC_PRESCAL (0x3f << 8) /* Prescalar Rate Selection */
#define ATMEL_TSADCC_EPRESCAL (0xff << 8) /* Prescalar Rate Selection (Extended) */
#define ATMEL_TSADCC_STARTUP (0x7f << 16) /* Start Up time */
#define ATMEL_TSADCC_SHTIM (0xf << 24) /* Sample & Hold time */
#define ATMEL_TSADCC_PENDBC (0xf << 28) /* Pen Detect debouncing time */
Expand Down Expand Up @@ -84,7 +88,13 @@
#define ATMEL_TSADCC_CDR4 0x40 /* Channel Data 4 */
#define ATMEL_TSADCC_CDR5 0x44 /* Channel Data 5 */

#define ADC_CLOCK 1000000
#define ATMEL_TSADCC_XPOS 0x50
#define ATMEL_TSADCC_Z1DAT 0x54
#define ATMEL_TSADCC_Z2DAT 0x58

#define PRESCALER_VAL(x) ((x) >> 8)

#define ADC_DEFAULT_CLOCK 100000

struct atmel_tsadcc {
struct input_dev *input;
Expand Down Expand Up @@ -172,6 +182,7 @@ static int __devinit atmel_tsadcc_probe(struct platform_device *pdev)
struct atmel_tsadcc *ts_dev;
struct input_dev *input_dev;
struct resource *res;
struct at91_tsadcc_data *pdata = pdev->dev.platform_data;
int err = 0;
unsigned int prsc;
unsigned int reg;
Expand Down Expand Up @@ -254,19 +265,37 @@ static int __devinit atmel_tsadcc_probe(struct platform_device *pdev)
prsc = clk_get_rate(ts_dev->clk);
dev_info(&pdev->dev, "Master clock is set at: %d Hz\n", prsc);

prsc = prsc / ADC_CLOCK / 2 - 1;
if (!pdata)
goto err_fail;

if (!pdata->adc_clock)
pdata->adc_clock = ADC_DEFAULT_CLOCK;

prsc = (prsc / (2 * pdata->adc_clock)) - 1;

/* saturate if this value is too high */
if (cpu_is_at91sam9rl()) {
if (prsc > PRESCALER_VAL(ATMEL_TSADCC_PRESCAL))
prsc = PRESCALER_VAL(ATMEL_TSADCC_PRESCAL);
} else {
if (prsc > PRESCALER_VAL(ATMEL_TSADCC_EPRESCAL))
prsc = PRESCALER_VAL(ATMEL_TSADCC_EPRESCAL);
}

dev_info(&pdev->dev, "Prescaler is set at: %d\n", prsc);

reg = ATMEL_TSADCC_TSAMOD_TS_ONLY_MODE |
((0x00 << 5) & ATMEL_TSADCC_SLEEP) | /* Normal Mode */
((0x01 << 6) & ATMEL_TSADCC_PENDET) | /* Enable Pen Detect */
((prsc << 8) & ATMEL_TSADCC_PRESCAL) | /* PRESCAL */
((0x13 << 16) & ATMEL_TSADCC_STARTUP) | /* STARTUP */
((0x0F << 28) & ATMEL_TSADCC_PENDBC); /* PENDBC */
(prsc << 8) |
((0x26 << 16) & ATMEL_TSADCC_STARTUP) |
((pdata->pendet_debounce << 28) & ATMEL_TSADCC_PENDBC);

atmel_tsadcc_write(ATMEL_TSADCC_CR, ATMEL_TSADCC_SWRST);
atmel_tsadcc_write(ATMEL_TSADCC_MR, reg);
atmel_tsadcc_write(ATMEL_TSADCC_TRGR, ATMEL_TSADCC_TRGMOD_NONE);
atmel_tsadcc_write(ATMEL_TSADCC_TSR, (0x3 << 24) & ATMEL_TSADCC_TSSHTIM);
atmel_tsadcc_write(ATMEL_TSADCC_TSR,
(pdata->ts_sample_hold_time << 24) & ATMEL_TSADCC_TSSHTIM);

atmel_tsadcc_read(ATMEL_TSADCC_SR);
atmel_tsadcc_write(ATMEL_TSADCC_IER, ATMEL_TSADCC_PENCNT);
Expand Down

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