[U-Boot] [PATCH v4 19/34] board: atmel: add support for pda detection

Eugen Hristev
2018-09-18T07:35:42Z

This adds the support for PDA detection as common code for
Atmel boards.
Using the one wire interface over GPIO , an EEPROM memory is read
and compared to preprogrammed values for PDA screens TM4300, TM7000
and TM7000B.
Once the PDA is detected, an environment variable is set accordingly.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
---
board/atmel/common/board.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)

diff --git a/board/atmel/common/board.c b/board/atmel/common/board.c
index 650eb22..8f9b5e1 100644
--- a/board/atmel/common/board.c
+++ b/board/atmel/common/board.c
@@ -5,7 +5,64 @@
*/

#include <common.h>
+#include <w1.h>
+#include <w1-eeprom.h>
+#include <dm/device-internal.h>
+
+#define AT91_PDA_EEPROM_ID_OFFSET 15
+#define AT91_PDA_EEPROM_ID_LENGTH 5
+#define AT91_PDA_EEPROM_DEFAULT_BUS 0

void dummy(void)
{
}
+
+#if defined CONFIG_W1
+void at91_pda_detect(void)
+{
+ struct udevice *bus, *dev;
+ u8 buf[AT91_PDA_EEPROM_ID_LENGTH + 1] = {0};
+ int ret;
+ int pda = 0;
+
+ ret = w1_get_bus(AT91_PDA_EEPROM_DEFAULT_BUS, &bus);
+ if (ret)
+ return;
+
+ for (device_find_first_child(bus, &dev);
+ dev;
+ device_find_next_child(&dev)) {
+ ret = device_probe(dev);
+ if (ret) {
+ continue;
+ } else {
+ ret = w1_eeprom_read_buf(dev, AT91_PDA_EEPROM_ID_OFFSET,
+ (u8 *)buf, AT91_PDA_EEPROM_ID_LENGTH);
+ if (ret)
+ return;
+ break;
+ }
+ }
+ pda = simple_strtoul((const char *)buf, NULL, 10);
+
+ switch (pda) {
+ case 7000:
+ if (buf[4] == 'B')
+ printf("PDA TM7000B detected\n");
+ else
+ printf("PDA TM7000 detected\n");
+ break;
+ case 4300:
+ printf("PDA TM4300 detected\n");
+ break;
+ case 5000:
+ printf("PDA TM5000 detected\n");
+ break;
+ }
+ env_set("pda", (const char *)buf);
+}
+#else
+void at91_pda_detect(void)
+{
+}
+#endif
--
2.7.4