5" Display For Raspberry Pi Pi2 Model B+ A+ used for OragePi 2

Jacaranda

You need compile ADS7846 touchscreen as a module.

fex:

1. [spi0]
   
2. spi_used = 1
   
3. spi_cs_bitmap = 1
   
4. spi_mosi = port:PC00<3><default><default><default>
   
5. spi_miso = port:PC01<3><default><default><default>
   
6. spi_sclk = port:PC02<3><default><default><default>
   
7. spi_cs0 = port:PA21<1><1><default><default>
   
8. 
   
9. [spi_devices]
   
10. spi_dev_num = 1
    
11. 
    
12. [spi_board0]
    
13. modalias = "ads7846"
    
14. max_speed_hz = 1500000
    
15. bus_num = 0
    
16. chip_select = 0
    
17. mode = 0
    
18. full_duplex = 1
    
19. manual_cs = 0
    

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drivers/input/touchscreen/ads7846.c:

1. diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads
   
2. index f02028e..0a3f610 100644
   
3. --- a/drivers/input/touchscreen/ads7846.c
   
4. +++ b/drivers/input/touchscreen/ads7846.c
   
5. @@ -59,6 +59,22 @@
   
6. #define TS_POLL_DELAY  1       /* ms delay before the first sample */
   
7. #define TS_POLL_PERIOD 5       /* ms delay between samples */
   
8. 
   
9. +
   
10. +static struct ads7846_platform_data ads7846_chip_info =
    
11. +{
    
12. +    .gpio_pendown      = 2,
    
13. +    .pressure_max      = 255,
    
14. +    .x_plate_ohms      = 180,
    
15. +    .x_min             = 176,
    
16. +    .x_max             = 3913,
    
17. +    .y_min             = 300,
    
18. +    .y_max             = 3947,
    
19. +    .debounce_max      = 10,
    
20. +    .debounce_tol      = 3,
    
21. +    .debounce_rep      = 1,
    
22. +    .keep_vref_on      = 1
    
23. +};
    
24. +
    
25. /* this driver doesn't aim at the peak continuous sample rate */
    
26. #define        SAMPLE_BITS     (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after
    
27. 
    
28. @@ -970,6 +986,7 @@ static int __devinit ads7846_setup_pendown(struct spi_device
    
29.                 ts->get_pendown_state = pdata->get_pendown_state;
    
30.         } else if (gpio_is_valid(pdata->gpio_pendown)) {
    
31. 
    
32. +               // try to get gpio for pendown
    
33.                 err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN,
    
34.                                        "ads7846_pendown");
    
35.                 if (err) {
    
36. @@ -1197,17 +1214,27 @@ static int __devinit ads7846_probe(struct spi_device *sp
    
37.         struct ads7846 *ts;
    
38.         struct ads7846_packet *packet;
    
39.         struct input_dev *input_dev;
    
40. +
    
41. +       if (!spi->dev.platform_data) {
    
42. +               spi->dev.platform_data = &ads7846_chip_info;
    
43. +       }
    
44. +
    
45.         struct ads7846_platform_data *pdata = spi->dev.platform_data;
    
46.         unsigned long irq_flags;
    
47.         int err;
    
48. 
    
49. -       if (!spi->irq) {
    
50. -               dev_dbg(&spi->dev, "no IRQ?\n");
    
51. +       if (!pdata) {
    
52. +               dev_dbg(&spi->dev, "no platform data?\n");
    
53.                 return -ENODEV;
    
54.         }
    
55. 
    
56. -       if (!pdata) {
    
57. -               dev_dbg(&spi->dev, "no platform data?\n");
    
58. +       // try to grab irq for pendown
    
59. +       if (pdata->gpio_pendown) {
    
60. +               spi->irq = gpio_to_irq(pdata->gpio_pendown);
    
61. +       }
    
62. +
    
63. +       if (!spi->irq) {
    
64. +               dev_dbg(&spi->dev, "no IRQ?\n");
    
65.                 return -ENODEV;
    
66.         }
    
67. 
    

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worked with PA21 - CS0 and PA02 - IRQ pendown.
Need some trics with platform_data, touch worked but no so cool.

Jacaranda

platform_data in ads7846 driver module it's not true way. If any body know how made it right, please correct me. Thanks

Jacaranda

PA21 - is CS0 and PA02 - is IRQ for pendown You need turn off uart2 used PA02

1. [uart2]
   
2. uart_used = 0
   
3. uart_port = 2
   
4. uart_type = 4
   
5. uart_tx = port:PA00<2><1><default><default>
   
6. uart_rx = port:PA01<2><1><default><default>
   
7. uart_rts = port:PA02<2><1><default><default>
   
8. uart_cts = port:PA03<2><1><default><default>
   

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loboris

Jacaranda replied at 2015-10-19 04:06
Wow thank you very much, can you share timig changes ?) thanks. Later i give driver code changes and ...

Thank you for sharing the code.
My display has USB touchscreen, but I would like to test the spi driver too.
You can get my sources at GitHub.

Jacaranda

loboris replied at 2015-10-19 20:02
Thank you for sharing the code.
My display has USB touchscreen, but I would like to test the spi d ...

Thanks for sources all work perfect.

Maxikose

Any idea how to get this display work with Android maybe Beelink_X2-SC_V1.1-Custom_ROM ? Its seems to be forced to use 1280x720 resolution...

igzero

loboris replied at 2015-10-19 20:02
Thank you for sharing the code.
My display has USB touchscreen, but I would like to test the spi d ...

Hi!"Orange PI PC" will work with this display ( http://www.aliexpress.com/item/I ... MI/32583337754.html ) if I use your drivers?

zgoda

This is HDMI connection interface for generic LCD display. For less than $30 I would try my luck.

leonidy-85

Jacaranda replied at 2015-10-19 07:51
platform_data in ads7846 driver module it's not true way. If any body know how made it right, please ...

Lay out please, the script.bin and ads7846.ko

tom1986

Hi, has anybody get this touchscreen working?