[U-Boot] [PATCH] dm: gpio: pca953x: introduce driver model support for pca953x

Michal Simek
2016-04-11T12:40:06Z

On 11.4.2016 14:09, Michal Simek wrote:
> On 11.4.2016 07:47, Peng Fan wrote:
>> On Sat, Apr 09, 2016 at 12:33:34PM -0600, Simon Glass wrote:
>>> On 18 March 2016 at 03:54, Peng Fan <van.freenix@gmail.com> wrote:
>>>> Introduce a new driver that supports driver model for pca953x.
>>>> The pca953x chips are used as I2C I/O expanders.
>>>> This driver is designed to support the following chips:
>>>> "
>>>> 4 bits: pca9536, pca9537
>>>> 8 bits: max7310, max7315, pca6107, pca9534, pca9538, pca9554,
>>>> pca9556, pca9557, pca9574, tca6408, xra1202
>>>> 16 bits: max7312, max7313, pca9535, pca9539, pca9555, pca9575,
>>>> tca6416
>>>> 24 bits: tca6424
>>>> 40 bits: pca9505, pca9698
>>>> "
>>>> But for now this driver only supports max 24 bits and pca953x compatible
>>>> chips. pca957x compatible chips are not supported now.
>>>> These can be addressed when we need to add such support for the different
>>>> chips.
>>>> This driver has been tested on i.MX6 SoloX Sabreauto board with max7310
>>>> i2c expander using gpio command as following:
>>>>
>>>> =>gpio status -a
>>>> Bank gpio at 48:
>>>> gpio at 480: input: 1 [ ]
>>>> => gpio clear gpio at 480
>>>> gpio: pin gpio at 480 (gpio 224) value is 0
>>>> => gpio status -a
>>>> Bank gpio at 48:
>>>> gpio at 480: output: 0 [ ]
>>>
>>> Don't you think 480 is confusing? Perhaps you should have gpio at 48_ as
>>> the bank name? Also I think you should support a gpio-bank-name
>>> property in the node, to allow a sensible name to be provided.
>>
>> 480 is added by gpio uclass driver I think.
>> The dts is copied from Linux side. I'd not change the dts, will try to
>> see how to introudce a sensible name here.
>
> What's the binding you are using?
>
> The part of this patch should be DT binding.
>
> This is my node.
> tca6416_u61: gpio at 21 {
> compatible = "ti,tca6416";
> reg = <0x21>;
> gpio-controller;
> #gpio-cells = <2>;
> };
>

Ok. I found where the problem is.

i2c bus has
#address-cells = <1>;
#size-cells = <0>;

And then OF_CHECK_COUNTS thinks that it is incorrect setting for bus
but it should be valid for i2c where only address without size is used.
When I apply patch below driver is probed

diff --git a/common/fdt_support.c b/common/fdt_support.c
index ced119e70d9f..5f5b49c6210b 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -941,7 +941,7 @@ void fdt_del_node_and_alias(void *blob, const char
*alias)
#define OF_MAX_ADDR_CELLS 4
#define OF_BAD_ADDR FDT_ADDR_T_NONE
#define OF_CHECK_COUNTS(na, ns) ((na) > 0 && (na) <=
OF_MAX_ADDR_CELLS && \
- (ns) > 0)
+ (ns) >= 0)

/* Debug utility */
#ifdef DEBUG

Regarding numbers. It is just hex to int conversion + gpio number.
It means gpio at 20 is 0x20 which is 32. Using hex everywhere make sense
and this is the fix. Maybe better to also use underscore.

diff --git a/drivers/gpio/pca953x_gpio.c b/drivers/gpio/pca953x_gpio.c
index 6b67b079a17b..1eeb4c8f199a 100644
--- a/drivers/gpio/pca953x_gpio.c
+++ b/drivers/gpio/pca953x_gpio.c
@@ -292,7 +292,7 @@ static int pca953x_probe(struct udevice *dev)
return ret;
}

- snprintf(name, sizeof(name), "gpio@%u", info->addr);
+ snprintf(name, sizeof(name), "gpio@%x_", info->addr);
str = strdup(name);
if (!str)
return -ENOMEM;

Output below.

Thanks,
Michal

ZynqMP> dm tree
Class Probed Name
----------------------------------------
root [ + ] root_driver
simple_bus [ ] |-- amba_apu
simple_bus [ + ] `-- amba
eth [ + ] |-- ethernet at ff0e0000
i2c [ + ] |-- i2c at ff020000
gpio [ + ] | |-- gpio at 20
gpio [ + ] | |-- gpio at 21
i2c_mux [ ] | `-- i2cswitch at 75
i2c [ ] | |-- i2c at 0
i2c [ ] | |-- i2c at 1
i2c [ ] | `-- i2c at 2
i2c [ ] |-- i2c at ff030000
i2c_mux [ ] | |-- i2cswitch at 74
i2c [ ] | | |-- i2c at 0
i2c [ ] | | |-- i2c at 1
i2c [ ] | | |-- i2c at 2
i2c [ ] | | |-- i2c at 3
i2c [ ] | | `-- i2c at 4
i2c_mux [ ] | `-- i2cswitch at 75
i2c [ ] | |-- i2c at 0
i2c [ ] | |-- i2c at 1
i2c [ ] | |-- i2c at 2
i2c [ ] | |-- i2c at 3
i2c [ ] | |-- i2c at 4
i2c [ ] | |-- i2c at 5
i2c [ ] | |-- i2c at 6
i2c [ ] | `-- i2c at 7
mmc [ + ] |-- sdhci at ff170000
serial [ + ] |-- serial at ff000000
serial [ ] `-- serial at ff010000
ZynqMP> i2c bus
Bus 0: i2c at ff020000 (active 0)
20: gpio at 20, offset len 1, flags 0
21: gpio at 21, offset len 1, flags 0
75: i2cswitch at 75, offset len 1, flags 0
Bus 750: i2c at 0
Bus 751: i2c at 1
Bus 752: i2c at 2
Bus 1: i2c at ff030000
74: i2cswitch at 74, offset len 1, flags 0
75: i2cswitch at 75, offset len 1, flags 0
Bus 750: i2c at 0
Bus 751: i2c at 1
Bus 752: i2c at 2
Bus 1743: i2c at 3
Bus 1744: i2c at 4
Bus 750: i2c at 0
Bus 751: i2c at 1
Bus 752: i2c at 2
Bus 1743: i2c at 3
Bus 1744: i2c at 4
Bus 1755: i2c at 5
Bus 1756: i2c at 6
Bus 1757: i2c at 7
ZynqMP> gpio status -a
Bank gpio at 20_:
gpio at 20_0: output: 1 [ ]
gpio at 20_1: output: 1 [ ]
gpio at 20_2: output: 1 [ ]
gpio at 20_3: output: 1 [ ]
gpio at 20_4: output: 0 [ ]
gpio at 20_5: output: 1 [ ]
gpio at 20_6: output: 1 [ ]
gpio at 20_7: output: 1 [ ]
gpio at 20_8: output: 0 [ ]
gpio at 20_9: output: 0 [ ]
gpio at 20_10: output: 0 [ ]
gpio at 20_11: output: 0 [ ]
gpio at 20_12: output: 0 [ ]
gpio at 20_13: output: 0 [ ]
gpio at 20_14: output: 0 [ ]
gpio at 20_15: output: 0 [ ]

Bank gpio at 21_:
gpio at 21_0: input: 1 [ ]
gpio at 21_1: input: 1 [ ]
gpio at 21_2: input: 1 [ ]
gpio at 21_3: input: 1 [ ]
gpio at 21_4: input: 1 [ ]
gpio at 21_5: input: 0 [ ]
gpio at 21_6: input: 0 [ ]
gpio at 21_7: input: 0 [ ]
gpio at 21_8: input: 0 [ ]
gpio at 21_9: input: 0 [ ]
gpio at 21_10: input: 0 [ ]
gpio at 21_11: input: 0 [ ]
gpio at 21_12: input: 0 [ ]
gpio at 21_13: input: 0 [ ]
gpio at 21_14: input: 0 [ ]
gpio at 21_15: input: 0 [ ]
ZynqMP>