Touchscreen for Beagleboard Rev C4 issue

Nguyen Huu Ha

Prodigy 130 points

Other Parts Discussed in Thread: ADS7846

Hi,

I am trying to configure my 7" TFT touch screen with Android 2.3.4

After I made some changes in board-omap3beagle.c like in porting guides, my board has recognized the device:

when booting:

spi3.0 supply vcc not found, using dummy regulator
ads7846 spi3.0: touchscreen, irq 293
input: ADS7846 Touchscreen as /devices/platform/omap2_mcspi.3/spi3.0/input/input1

and I use "getevent":

add device 1: /dev/input/event1
name: "ADS7846 Touchscreen"
could not get driver version for /dev/input/mouse0, Not a typewriter

however, when I touch, no event is happened and it does not work at all,

Could you please give me some suggestions for this issue

I connect it through expansion header, I think I use spi3.0 . Not sure with this question but I will provide what I did.

Here's my spi_board_info:

struct spi_board_info omap3evm_spi_board_info[] = {
[0] = {
.modalias = "ads7846",
.bus_num = 3,
.chip_select = 0,
.max_speed_hz = 1500000,
.controller_data = &ads7846_mcspi_config,
.irq = OMAP_GPIO_IRQ(OMAP3_EVM_TS_GPIO),
.platform_data = &ads7846_config,
},
};

static struct omap2_mcspi_device_config ads7846_mcspi_config = {
.turbo_mode = 0,
.single_channel = 1, /* 0: slave, 1: master */
};

struct ads7846_platform_data ads7846_config = {
.x_max = 0x0fff,
.y_max = 0x0fff,
.x_plate_ohms = 180,
.pressure_max = 255,
.debounce_max = 10,
.debounce_tol = 3,
.debounce_rep = 1,
.get_pendown_state = ads7846_get_pendown_state,
.keep_vref_on = 1,
.settle_delay_usecs = 150,
.wakeup = true,
};

over 13 years ago

Vishveshwar Bhat over 13 years ago

TI__Genius 10210 points

See http://e2e.ti.com/support/embedded/f/509/t/132452.aspx

Nguyen Huu Ha over 13 years ago in reply to Vishveshwar Bhat

Prodigy 130 points

I have tested "cat /proc/interrupts" commands and found:

the CPU0 value increases each time I touch in the screen ?

In this topic, the problem is solved by configuring touch sensor for SPI 3.0. Could you show me how to configure it ?

Thank you very much.

Vishveshwar Bhat over 13 years ago in reply to Nguyen Huu Ha

TI__Genius 10210 points

I recommend to verify with the touchscreen/spi settings for omap3evm:

http://gitorious.org/rowboat/kernel/blobs/rowboat-kernel-2.6.37/arch/arm/mach-omap2/board-omap3evm.c

Look for static struct spi_board_info omap3evm_spi_board_info[]

You can also go through our porting guide:

http://processors.wiki.ti.com/index.php/TI-Android-GingerBread-2.3.4-DevKit-2.1_PortingGuides#Touchscreen

Faisal Hassan over 13 years ago in reply to Vishveshwar Bhat

Intellectual 255 points

Hi Nguyen Huu Ha,

Can you make sure that, your touchsensor is connected to the spi 3.0. Check the expansion board schematics.

Then you have to add one regulator supply for that. And also multiplux those lines as spi.

Thanks,

Faisal Hassan

Nguyen Huu Ha over 13 years ago in reply to Faisal Hassan

Prodigy 130 points

Actually I have the source configured for beagleboard xm in android 2.2, and made some changes according to board-omap3beagle.c ( some changes were updated in first post )

Therefore, I think my touchsensor is connected to the spi 3.0. In addition, I think I have added SPI support following this link ( http://elinux.org/BeagleBoard/SPI#Configuring_Pinmux) :

struct spi_board_info omap3evm_spi_board_info[] = {
[0] = {
.modalias = "ads7846",
.bus_num = 3,
.chip_select = 0,
.max_speed_hz = 1500000,
.controller_data = &ads7846_mcspi_config,
.irq = OMAP_GPIO_IRQ(OMAP3_EVM_TS_GPIO),
.platform_data = &ads7846_config,
},
};

What do you configure for touchsensor to SPI 3.0 ?

Thank you.

Faisal Hassan over 13 years ago in reply to Nguyen Huu Ha

Intellectual 255 points

Hi Nguyen Huu Ha,

Apart from these changes i included one regulator supply (vio).
Here is the patch

@@ -284,6 +294,11 @@
static struct regulator_consumer_supply beagle_vdvi_supply =
REGULATOR_SUPPLY("vdds_dsi", "omapdss");
+
+/* ads7846 on SPI */
+static struct regulator_consumer_supply beagle_vio_supply =
+ REGULATOR_SUPPLY("vcc", "spi3.0");

static void __init beagle_display_init(void)
{
@@ -492,6 +507,22 @@
.consumer_supplies = &beagle_vaux3_supply,
};
+
+/* VIO for ads7846 and nubs */
+static struct regulator_init_data beagle_vio = {
+ .constraints = {
+ .min_uV = 1800000,
+ .max_uV = 1800000,
+ .apply_uV = true,
+ .valid_modes_mask = REGULATOR_MODE_NORMAL
+ | REGULATOR_MODE_STANDBY,
+ .valid_ops_mask = REGULATOR_CHANGE_MODE
+ | REGULATOR_CHANGE_STATUS,
+ },
+ .num_consumer_supplies = 1,
+ .consumer_supplies = &beagle_vio_supply,
+};
+
/* VAUX4 for CAM_2V8 */
static struct regulator_init_data beagle_vaux4 = {
.constraints = {
@@ -534,6 +565,8 @@
.vpll2 = &beagle_vpll2,
.vaux3 = &beagle_vaux3,
.vaux4 = &beagle_vaux4,
+ .vio = &beagle_vio,
};

Thanks,
Faisal Hassan

Baker Huang over 13 years ago in reply to Nguyen Huu Ha

Intellectual 360 points

Hi,

How can I know the touch sensor connected to spi 3.0 or spi 1.0 ,Can you tell me the difference between spi 1.0 & spi 3.0 ,Thanks .

Nguyen Huu Ha over 13 years ago in reply to Baker Huang

Prodigy 130 points

Hi Baker Huang, You can find the configuration in kernel\arch\arm\mach-omap2\board-omap3beagle.c . Moreover, you should read following link http://elinux.org/BeagleBoard/SPI#Configuring_Pinmux and board manual for more details. Good luck.

Subrat Ojha over 13 years ago in reply to Faisal Hassan

Prodigy 185 points

Hi faisal,

i follwed ur post and corrected every area but i didnt get why you included the vio in the structure that doesnot have any such elements.Please let me know if any further changes required in that structure.

However for the time being i included in twl_4030 .But i am not getting any interrupts.

Thanks and regards

subrat Kumar Ojha

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Touchscreen for Beagleboard Rev C4 issue