[U-Boot] [PATCH 1/3] dm: i2c soft: enable driver model for software i2c driver
Heiko Schocher
hs at denx.de
Tue Mar 24 07:01:33 CET 2015
Hello Simon, Przemyslaw,
Am 24.03.2015 00:38, schrieb Simon Glass:
> Hi Przemyslaw,
>
> On 10 March 2015 at 04:30, Przemyslaw Marczak <p.marczak at samsung.com> wrote:
>> This change adds driver model support to software emulated
>> i2c bus driver. To bind the driver, proper device-tree node
>> must be defined, with the following attributes:
>> - alias: to keep proper bus order
>> - compatible: 'soft-i2c'
>> - clock-frequency [Hz]
>> - clock-pin, data-pin: gpio phandles
>>
>> /* Define the alias number to keep bus numbering order */
>> aliases {
>> [...]
>> i2c5 = "/i2c at 13500000";
>> i2c6 = "/soft-i2c at 1";
>> [...]
>> };
>>
>> /* Define the basic bus attributes */
>> soft-i2c at 1 {
>> #address-cells = <1>;
>> #size-cells = <0>;
>> compatible = "soft-i2c";
>> clock-frequency = <50000>;
>>
>> /* Define the proper GPIO pins */
>> clock-pin = <&gpa0 0 GPIO_ACTIVE_HIGH>;
>> data-pin = <&gpa0 1 GPIO_ACTIVE_HIGH>;
>>
>> /* Optionally, define some driver node (bus child) */
>> somedev at 0x44 {
>> compatible = "somedev";
>> reg = <0x44>;
>> [...]
>> };
>> };
>>
>> The device can be accessed by the i2c command:
>> i2c dev 8 (bus number set by alias)
>> i2c probe <0x44> (address is optionally)
>> i2c md 0x44 0x0 (dump dev registers at address 0x0)
>> Valid chip addresses: 0x44 (success!)
>> ...
>>
>> The previous driver functionality stays unchanged. Driving the bus lines
>> is done by dm gpio calls in the preprocessor macros. Each, can be redefined
>> by the user as previous.
>>
>> Tested on Trats2 and Odroid U3.
>
> Is the intention to retire the old (non-driver-model) code? What boards use it?
I think not ... Hmm ... maybe you move the new code into
a new file?
>> Signed-off-by: Przemyslaw Marczak <p.marczak at samsung.com>
>> Cc: Masahiro Yamada <yamada.m at jp.panasonic.com>
>> Cc: Mike Frysinger <vapier at gentoo.org>
>> Cc: Simon Glass <sjg at chromium.org>
>> Cc: Heiko Schocher <hs at denx.de>
Hups... seems I missed this patches ...
>> ---
>> drivers/i2c/Makefile | 1 +
>> drivers/i2c/soft_i2c.c | 410 +++++++++++++++++++++++++++++++++++++++++++++++--
>> 2 files changed, 400 insertions(+), 11 deletions(-)
Thanks for this work!
>> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
>> index 774bc94..7039b6d 100644
>> --- a/drivers/i2c/Makefile
>> +++ b/drivers/i2c/Makefile
>> @@ -6,6 +6,7 @@
>> #
>> obj-$(CONFIG_DM_I2C) += i2c-uclass.o
>> obj-$(CONFIG_DM_I2C_COMPAT) += i2c-uclass-compat.o
>> +obj-$(CONFIG_DM_I2C_SOFT) += soft_i2c.o
>>
>> obj-$(CONFIG_SYS_I2C_ADI) += adi_i2c.o
>> obj-$(CONFIG_I2C_MV) += mv_i2c.o
>> diff --git a/drivers/i2c/soft_i2c.c b/drivers/i2c/soft_i2c.c
>> index db9b402..7afae0b 100644
>> --- a/drivers/i2c/soft_i2c.c
>> +++ b/drivers/i2c/soft_i2c.c
>> @@ -1,4 +1,7 @@
>> /*
>> + * (C) Copyright 2015, Samsung Electronics
>> + * Przemyslaw Marczak <p.marczak at samsung.com>
>> + *
>> * (C) Copyright 2009
>> * Heiko Schocher, DENX Software Engineering, hs at denx.de.
>> * Changes for multibus/multiadapter I2C support.
>> @@ -14,6 +17,11 @@
>> */
>>
>> #include <common.h>
>> +#include <errno.h>
>> +#include <dm.h>
>> +#include <i2c.h>
>> +#include <div64.h>
>> +#include <asm/gpio.h>
>> #ifdef CONFIG_MPC8260 /* only valid for MPC8260 */
>> #include <ioports.h>
>> #include <asm/io.h>
>> @@ -32,11 +40,9 @@
>> #if defined(CONFIG_MPC852T) || defined(CONFIG_MPC866)
>> #include <asm/io.h>
>> #endif
>> -#include <i2c.h>
>>
>> +#if defined(CONFIG_SYS_I2C)
>> #if defined(CONFIG_SOFT_I2C_GPIO_SCL)
>> -# include <asm/gpio.h>
>> -
>> # ifndef I2C_GPIO_SYNC
>> # define I2C_GPIO_SYNC
>> # endif
>> @@ -85,6 +91,7 @@
>> # endif
>>
>> #endif
>> +#endif
>>
>> /* #define DEBUG_I2C */
>>
>> @@ -109,6 +116,65 @@ DECLARE_GLOBAL_DATA_PTR;
>> #define CONFIG_SYS_I2C_SOFT_SLAVE CONFIG_SYS_I2C_SLAVE
>> #endif
>>
>> +/* DM SOFT I2C */
>> +#ifdef CONFIG_DM_I2C_SOFT
>> +# ifndef I2C_GPIO_SYNC
>> +# define I2C_GPIO_SYNC(gpio)
>> +# endif
>> +
>> +# ifndef I2C_INIT
>> +# define I2C_INIT(scl, sda) \
>> + do { } while (0)
>> +# endif
>> +
>> +# ifndef I2C_ACTIVE
>> +# define I2C_ACTIVE(sda) \
>> + do { } while (0)
>> +# endif
>> +
>> +# ifndef I2C_TRISTATE
>> +# define I2C_TRISTATE(sda) \
>> + do { } while (0)
>> +# endif
>> +
>> +# ifndef I2C_READ
>> +# define I2C_READ(sda) dm_gpio_get_value(sda);
>> +# endif
>> +
>> +# ifndef I2C_SDA
>> +# define I2C_SDA(sda, bit) \
>> + do { \
>> + if (bit) { \
>> + sda->flags &= ~GPIOD_IS_OUT; \
>> + sda->flags |= GPIOD_IS_IN; \
>> + dm_gpio_set_dir(sda); \
>> + } else { \
>> + sda->flags &= ~GPIOD_IS_IN; \
>> + sda->flags |= GPIOD_IS_OUT; \
>> + dm_gpio_set_dir(sda); \
>> + dm_gpio_set_value(sda, 0); \
>> + } \
>> + I2C_GPIO_SYNC(sda); \
>> + } while (0)
>> +# endif
>> +
>> +# ifndef I2C_SCL
>> +# define I2C_SCL(scl, bit) \
>> + do { \
>> + scl->flags &= ~GPIOD_IS_IN; \
>> + scl->flags |= GPIOD_IS_OUT; \
>> + dm_gpio_set_dir(scl); \
>> + dm_gpio_set_value(scl, bit); \
>> + I2C_GPIO_SYNC(scl); \
>> + } while (0)
>> +# endif
>> +
>> +# ifndef I2C_DELAY
>> +# define I2C_DELAY(us) udelay(us) /* 1/4 I2C clock duration */
>> +# endif
>> +
>> +#endif /* CONFIG_DM_I2C_SOFT */
>> +
>> /*-----------------------------------------------------------------------
>> * Definitions
>> */
>> @@ -117,7 +183,6 @@ DECLARE_GLOBAL_DATA_PTR;
>> #define I2C_ACK 0 /* PD_SDA level to ack a byte */
>> #define I2C_NOACK 1 /* PD_SDA level to noack a byte */
>>
>> -
>> #ifdef DEBUG_I2C
>> #define PRINTD(fmt,args...) do { \
>> printf (fmt ,##args); \
>> @@ -129,21 +194,30 @@ DECLARE_GLOBAL_DATA_PTR;
>> /*-----------------------------------------------------------------------
>> * Local functions
>> */
>> +#ifdef CONFIG_SYS_I2C
>> #if !defined(CONFIG_SYS_I2C_INIT_BOARD)
>> -static void send_reset (void);
>> +static void send_reset(void);
>> +#endif
>> +static void send_start(void);
>> +static void send_stop(void);
>> +static void send_ack(int);
>> +static int write_byte(uchar byte);
>> +static uchar read_byte(int);
>> +#else
>> +static void send_reset(struct gpio_desc *, struct gpio_desc *, int);
>> +static void send_start(struct gpio_desc *, struct gpio_desc *, int);
>> +static void send_stop(struct gpio_desc *, struct gpio_desc *, int);
>> +static void send_ack(struct gpio_desc *, struct gpio_desc *, int, int);
>> +static int write_byte(struct gpio_desc *, struct gpio_desc *, int, uchar);
>> +static uchar read_byte(struct gpio_desc *, struct gpio_desc *, int, int);
>> #endif
>> -static void send_start (void);
>> -static void send_stop (void);
>> -static void send_ack (int);
>> -static int write_byte (uchar byte);
>> -static uchar read_byte (int);
>> -
>> #if !defined(CONFIG_SYS_I2C_INIT_BOARD)
>> /*-----------------------------------------------------------------------
>> * Send a reset sequence consisting of 9 clocks with the data signal high
>> * to clock any confused device back into an idle state. Also send a
>> * <stop> at the end of the sequence for belts & suspenders.
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static void send_reset(void)
>> {
>> I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> @@ -166,11 +240,36 @@ static void send_reset(void)
>> send_stop();
>> I2C_TRISTATE;
>> }
>> +#else
>> +static void send_reset(struct gpio_desc *scl, struct gpio_desc *sda, int delay)
>> +{
>> + I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> + int j;
>> +
>> + I2C_SCL(scl, 1);
>> + I2C_SDA(sda, 1);
>> +#ifdef I2C_INIT
>> + I2C_INIT(scl, sda);
>> +#endif
>> + I2C_TRISTATE(sda);
>> + for (j = 0; j < 9; j++) {
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 1);
>> + I2C_DELAY(delay);
>> + I2C_DELAY(delay);
>> + }
>> + send_stop(scl, sda, delay);
>> + I2C_TRISTATE(sda);
>
> For the new code I would much prefer that these become functions
> rather than macros. What is the benefit of using a macro?
I do not know the real reason, but I think it comes from powerpc
times, where we had not yet such powerful SoCs and it saved some
instructions ... I tend to say, lets move the dm part into a new
file ... and let it us do like linux ...
@Simon: Do you pick up this patches through DM tree, or should
I pick them up?
bye,
Heiko
>> +}
>> +#endif /* CONFIG_SYS_I2C_SOFT */
>> #endif
>>
>> /*-----------------------------------------------------------------------
>> * START: High -> Low on SDA while SCL is High
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static void send_start(void)
>> {
>> I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> @@ -184,10 +283,25 @@ static void send_start(void)
>> I2C_SDA(0);
>> I2C_DELAY;
>> }
>> +#else
>> +static void send_start(struct gpio_desc *scl, struct gpio_desc *sda, int delay)
>> +{
>> + I2C_SOFT_DECLARATIONS /* intentional without ';' */
>>
>> + I2C_DELAY(delay);
>> + I2C_SDA(sda, 1);
>> + I2C_ACTIVE(sda);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 1);
>> + I2C_DELAY(delay);
>> + I2C_SDA(sda, 0);
>> + I2C_DELAY(delay);
>> +}
>> +#endif /* CONFIG_SYS_I2C_SOFT */
>> /*-----------------------------------------------------------------------
>> * STOP: Low -> High on SDA while SCL is High
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static void send_stop(void)
>> {
>> I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> @@ -203,10 +317,28 @@ static void send_stop(void)
>> I2C_DELAY;
>> I2C_TRISTATE;
>> }
>> +#else
>> +static void send_stop(struct gpio_desc *scl, struct gpio_desc *sda, int delay)
>> +{
>> + I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> +
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> + I2C_SDA(sda, 0);
>> + I2C_ACTIVE(sda);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 1);
>> + I2C_DELAY(delay);
>> + I2C_SDA(sda, 1);
>> + I2C_DELAY(delay);
>> + I2C_TRISTATE(sda);
>> +}
>> +#endif /* CONFIG_SYS_I2C_SOFT */
>>
>> /*-----------------------------------------------------------------------
>> * ack should be I2C_ACK or I2C_NOACK
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static void send_ack(int ack)
>> {
>> I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> @@ -222,10 +354,29 @@ static void send_ack(int ack)
>> I2C_SCL(0);
>> I2C_DELAY;
>> }
>> +#else
>> +static void send_ack(struct gpio_desc *scl, struct gpio_desc *sda,
>> + int delay, int ack)
>> +{
>> + I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> +
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> + I2C_ACTIVE(sda);
>> + I2C_SDA(sda, ack);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 1);
>> + I2C_DELAY(delay);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> +}
>> +#endif
>>
>> /*-----------------------------------------------------------------------
>> * Send 8 bits and look for an acknowledgement.
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static int write_byte(uchar data)
>> {
>> I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> @@ -263,11 +414,52 @@ static int write_byte(uchar data)
>>
>> return(nack); /* not a nack is an ack */
>> }
>> +#else
>> +static int write_byte(struct gpio_desc *scl, struct gpio_desc *sda,
>> + int delay, uchar data)
>> +{
>> + I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> + int j;
>> + int nack;
>> +
>> + I2C_ACTIVE(sda);
>> + for (j = 0; j < 8; j++) {
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> + I2C_SDA(sda, data & 0x80);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 1);
>> + I2C_DELAY(delay);
>> + I2C_DELAY(delay);
>> +
>> + data <<= 1;
>> + }
>> +
>> + /*
>> + * Look for an <ACK>(negative logic) and return it.
>> + */
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> + I2C_SDA(sda, 1);
>> + I2C_TRISTATE(sda);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 1);
>> + I2C_DELAY(delay);
>> + I2C_DELAY(delay);
>> + nack = I2C_READ(sda);
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> + I2C_ACTIVE(sda);
>> +
>> + return nack; /* not a nack is an ack */
>> +}
>> +#endif
>>
>> /*-----------------------------------------------------------------------
>> * if ack == I2C_ACK, ACK the byte so can continue reading, else
>> * send I2C_NOACK to end the read.
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static uchar read_byte(int ack)
>> {
>> I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> @@ -293,10 +485,38 @@ static uchar read_byte(int ack)
>>
>> return(data);
>> }
>> +#else
>> +static uchar read_byte(struct gpio_desc *scl, struct gpio_desc *sda,
>> + int delay, int ack)
>> +{
>> + I2C_SOFT_DECLARATIONS /* intentional without ';' */
>> + int data;
>> + int j;
>> +
>> + /*
>> + * Read 8 bits, MSB first.
>> + */
>> + I2C_TRISTATE(sda);
>> + I2C_SDA(sda, 1);
>> + data = 0;
>> + for (j = 0; j < 8; j++) {
>> + I2C_SCL(scl, 0);
>> + I2C_DELAY(delay);
>> + I2C_SCL(scl, 1);
>> + I2C_DELAY(delay);
>> + data <<= 1;
>> + data |= I2C_READ(sda);
>> + I2C_DELAY(delay);
>> + }
>> + send_ack(scl, sda, delay, ack);
>>
>> + return data;
>> +}
>> +#endif /* CONFIG_SYS_I2C_SOFT */
>> /*-----------------------------------------------------------------------
>> * Initialization
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static void soft_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
>> {
>> #if defined(CONFIG_SYS_I2C_INIT_BOARD)
>> @@ -314,12 +534,14 @@ static void soft_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
>> send_reset ();
>> #endif
>> }
>> +#endif
>>
>> /*-----------------------------------------------------------------------
>> * Probe to see if a chip is present. Also good for checking for the
>> * completion of EEPROM writes since the chip stops responding until
>> * the write completes (typically 10mSec).
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static int soft_i2c_probe(struct i2c_adapter *adap, uint8_t addr)
>> {
>> int rc;
>> @@ -334,10 +556,12 @@ static int soft_i2c_probe(struct i2c_adapter *adap, uint8_t addr)
>>
>> return (rc ? 1 : 0);
>> }
>> +#endif
>>
>> /*-----------------------------------------------------------------------
>> * Read bytes
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static int soft_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
>> int alen, uchar *buffer, int len)
>> {
>> @@ -409,10 +633,12 @@ static int soft_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
>> send_stop();
>> return(0);
>> }
>> +#endif
>>
>> /*-----------------------------------------------------------------------
>> * Write bytes
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> static int soft_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
>> int alen, uchar *buffer, int len)
>> {
>> @@ -444,10 +670,12 @@ static int soft_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
>> send_stop();
>> return(failures);
>> }
>> +#endif
>>
>> /*
>> * Register soft i2c adapters
>> */
>> +#ifdef CONFIG_SYS_I2C_SOFT
>> U_BOOT_I2C_ADAP_COMPLETE(soft0, soft_i2c_init, soft_i2c_probe,
>> soft_i2c_read, soft_i2c_write, NULL,
>> CONFIG_SYS_I2C_SOFT_SPEED, CONFIG_SYS_I2C_SOFT_SLAVE,
>> @@ -473,3 +701,163 @@ U_BOOT_I2C_ADAP_COMPLETE(soft3, soft_i2c_init, soft_i2c_probe,
>> CONFIG_SYS_I2C_SOFT_SLAVE_4,
>> 3)
>> #endif
>> +#endif /* CONFIG_SYS_I2C_SOFT */
>> +
>> +#ifdef CONFIG_DM_I2C_SOFT
>> +struct soft_i2c_bus {
>> + unsigned int speed;
>> + unsigned long delay;
>> + struct gpio_desc scl;
>> + struct gpio_desc sda;
>> +};
>> +
>> +static int i2c_write_data(struct soft_i2c_bus *i2c_bus, uchar chip,
>> + uchar *buffer, int len, bool end_with_repeated_start)
>> +{
>> + struct gpio_desc *scl = &i2c_bus->scl;
>> + struct gpio_desc *sda = &i2c_bus->sda;
>> + unsigned int delay = i2c_bus->delay;
>> + int failures = 0;
>> +
>> + PRINTD("%s: chip %x buffer %p len %d\n", __func__, chip, buffer, len);
>> +
>> + send_start(scl, sda, delay);
>> + if (write_byte(scl, sda, delay, chip << 1)) {
>> + send_stop(scl, sda, delay);
>> + PRINTD("i2c_write, no chip responded %02X\n", chip);
>> + return -ENODEV;
>
> -EIO I think
>
>> + }
>> +
>> + while (len-- > 0) {
>> + if (write_byte(scl, sda, delay, *buffer++))
>> + failures++;
>> + }
>> +
>> + send_stop(scl, sda, delay);
>> +
>> + return failures;
>> +}
>> +
>> +static int i2c_read_data(struct soft_i2c_bus *i2c_bus, uchar chip,
>> + uchar *buffer, int len)
>> +{
>> + struct gpio_desc *scl = &i2c_bus->scl;
>> + struct gpio_desc *sda = &i2c_bus->sda;
>> + unsigned int delay = i2c_bus->delay;
>> +
>> + PRINTD("%s: chip %x buffer: %x len %d\n", __func__, chip, buffer, len);
>> +
>> + send_start(scl, sda, delay);
>> + write_byte(scl, sda, delay, (chip << 1) | 1); /* read cycle */
>> +
>> + while (len-- > 0)
>> + *buffer++ = read_byte(scl, sda, delay, len == 0);
>> +
>> + send_stop(scl, sda, delay);
>> +
>> + return 0;
>> +}
>> +
>> +static int soft_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs)
>> +{
>> + struct soft_i2c_bus *i2c_bus = dev_get_priv(dev);
>> + int ret;
>> +
>> + for (; nmsgs > 0; nmsgs--, msg++) {
>> + bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD);
>> + if (msg->flags & I2C_M_RD) {
>> + ret = i2c_read_data(i2c_bus, msg->addr, msg->buf,
>> + msg->len);
>> + } else {
>> + ret = i2c_write_data(i2c_bus, msg->addr, msg->buf,
>> + msg->len, next_is_read);
>> + }
>> + if (ret)
>> + return -EREMOTEIO;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int soft_i2c_probe(struct udevice *dev, uint chip, uint chip_flags)
>> +{
>> + struct soft_i2c_bus *i2c_bus = dev_get_priv(dev);
>> + struct gpio_desc *scl = &i2c_bus->scl;
>> + struct gpio_desc *sda = &i2c_bus->sda;
>> + unsigned int delay = i2c_bus->delay;
>> + int ret;
>> +
>> + send_start(scl, sda, delay);
>> + ret = write_byte(scl, sda, delay, (chip << 1) | 0);
>> + send_stop(scl, sda, delay);
>> +
>> + PRINTD("%s: bus: %d (%s) chip: %x flags: %x ret: %d\n",
>> + __func__, dev->seq, dev->name, chip, chip_flags, ret);
>> +
>> + return ret;
>> +}
>> +
>> +static int soft_i2c_set_bus_speed(struct udevice *dev, unsigned int speed)
>> +{
>> + struct soft_i2c_bus *i2c_bus = dev_get_priv(dev);
>> + struct gpio_desc *scl = &i2c_bus->scl;
>> + struct gpio_desc *sda = &i2c_bus->sda;
>> +
>> + i2c_bus->speed = speed;
>> + i2c_bus->delay = lldiv(1000000, speed << 2);
>> +
>> + (scl, sda, i2c_bus->delay);
>> +
>> + PRINTD("%s: bus: %d (%s) speed: %u Hz (1/4 of period: %lu us)\n",
>> + __func__, dev->seq, dev->name, speed, i2c_bus->delay);
>> +
>> + return 0;
>> +}
>> +
>> +static int soft_i2c_ofdata_to_platdata(struct udevice *dev)
>> +{
>> + struct soft_i2c_bus *i2c_bus = dev_get_priv(dev);
>> + const void *blob = gd->fdt_blob;
>> + char *pin_name;
>> + int ret;
>> +
>> + pin_name = "clock-pin";
>
> nit: You don't need this variable
>
>> + ret = gpio_request_by_name_nodev(blob, dev->of_offset, pin_name,
>> + 0, &i2c_bus->scl, GPIOD_IS_OUT);
>
> You should not use the nodev version when you have a device. Also below.
>
>> + if (ret)
>> + goto error;
>> +
>> + pin_name = "data-pin";
>
> nit: or here
>
>> + ret = gpio_request_by_name_nodev(blob, dev->of_offset, pin_name,
>> + 0, &i2c_bus->sda, GPIOD_IS_OUT);
>> + if (ret)
>> + goto error;
>> +
>> + PRINTD("%s: bus: %d (%s) fdt node ok\n", __func__, dev->seq, dev->name);
>> +
>> + return 0;
>> +error:
>> + error("Can't get %s for soft i2c dev: %s", pin_name, dev->name);
>> + return ret;
>> +}
>> +
>> +static const struct dm_i2c_ops soft_i2c_ops = {
>> + .xfer = soft_i2c_xfer,
>> + .probe_chip = soft_i2c_probe,
>> + .set_bus_speed = soft_i2c_set_bus_speed,
>> +};
>> +
>> +static const struct udevice_id soft_i2c_ids[] = {
>> + { .compatible = "soft-i2c" },
>> + { }
>> +};
>> +
>> +U_BOOT_DRIVER(soft_i2c) = {
>> + .name = "soft-i2c",
>> + .id = UCLASS_I2C,
>> + .of_match = soft_i2c_ids,
>> + .ofdata_to_platdata = soft_i2c_ofdata_to_platdata,
>> + .priv_auto_alloc_size = sizeof(struct soft_i2c_bus),
>> + .ops = &soft_i2c_ops,
>> +};
>> +#endif /* CONFIG_DM_I2C_SOFT */
>> --
>> 1.9.1
>>
>
> Regards,
> Simon
>
--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
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