MIPS: dts: qemu-malta.dts: use i2c-gpio for accessing CBUS FPGA I2C bus
Also we can enable m24c02 eeprom chip in dts-file e.g. &i2c0 { status = "okay"; eeprom: m24c02@50 { compatible = "spd"; reg = <0x50>; }; }; Alas! qemu mips malta spd m24c02 eeprom chip emulation is not perfect: the block read operation does not work properly. Here is an example. If we read eeprom content byte-by-byte then there is no problem: barebox:/ for i in 0x08 0x09 0x0a 0x0b 0x0c 0x0d 0x0e 0x0f ; > do i2c_read -b 0 -a 0x50 -r $i -c 1 ; done 0x01 0x75 0x54 0x00 0x82 0x08 0x00 0x01 Compare this output with content of qemu.git/hw/mips/mips_malta.c: static eeprom24c0x_t spd_eeprom = { .contents = { ... /* 00000008: */ 0x01,0x75,0x54,0x00,0x82,0x08,0x00,0x01, But if we read several bytes at once the we have data corruption: barebox:/ i2c_read -b 0 -a 0x50 -r 0x8 -c 8 0x01 0xff 0xff 0xff 0xff 0xff 0xff 0xff Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
parent
3ad9434f2f
commit
51cc423920
|
@ -32,6 +32,18 @@
|
|||
#gpio-cells = <2>;
|
||||
};
|
||||
|
||||
i2c0: i2c0 {
|
||||
compatible = "i2c-gpio";
|
||||
gpios = <&gpio 0 0 /* sda */
|
||||
&gpio 1 0 /* scl */
|
||||
>;
|
||||
i2c-gpio,sda-open-drain;
|
||||
i2c-gpio,scl-open-drain;
|
||||
#address-cells = <1>;
|
||||
#size-cells = <0>;
|
||||
status = "disabled";
|
||||
};
|
||||
|
||||
uart2: serial@bf000900 {
|
||||
compatible = "ns16550a";
|
||||
reg = <0xbf000900 0x40>;
|
||||
|
@ -58,3 +70,7 @@
|
|||
};
|
||||
};
|
||||
};
|
||||
|
||||
&i2c0 {
|
||||
status = "okay";
|
||||
};
|
||||
|
|
Loading…
Reference in New Issue