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Re: [lcd4linux] [PATCH] drv_HD44780: add 8bit i2c mode for HD44780
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From: Michael R. <mi...@re...> - 2015-06-18 17:12:09
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Patch has been applied an checked in. Thanks a lot!
Am 2015-06-18 um 18:00 schrieb Michael Grzeschik:
> From: Michael Grzeschik <m.g...@pe...>
>
> This patch adds support for dual i2c io-expander
> based 8bit support for HD44780. It multiplexes the
> switch between the data and databits.
>
> Signed-off-by: Michael Grzeschik <m.g...@pe...>
> ---
> drv_HD44780.c | 82 ++++++++++++++++++++++++++++++++++++++-----------------
> drv_generic_i2c.c | 65 +++++++++++++++++++++++++++++++++----------
> drv_generic_i2c.h | 2 +-
> 3 files changed, 109 insertions(+), 40 deletions(-)
>
> diff --git a/drv_HD44780.c b/drv_HD44780.c
> index 26f0bc9..7f4a56a 100644
> --- a/drv_HD44780.c
> +++ b/drv_HD44780.c
> @@ -706,10 +706,10 @@ static void drv_HD_PP_stop(void)
>
> */
>
> -static void drv_HD_I2C_nibble(unsigned char controller, unsigned char nibble)
> +static void drv_HD_I2C(unsigned char controller, unsigned char byte, int rs, int rw)
> {
> unsigned char enable;
> - unsigned char command; /* this is actually the first data byte on the PCF8574 */
> + unsigned char command = 0; /* this is actually the first data byte on the PCF8574 */
> unsigned char data_block[2];
> /* enable signal: 'controller' is a bitmask */
> /* bit n .. send to controller #n */
> @@ -738,28 +738,51 @@ static void drv_HD_I2C_nibble(unsigned char controller, unsigned char nibble)
> The main advantage we see is that we do 2 less IOCTL's from our driver.
> */
>
> - command = nibble;
> - data_block[0] = nibble | enable;
> - data_block[1] = nibble;
> + if (Bits == 4) {
> + if (rw)
> + byte |= SIGNAL_RW;
> + if (rs)
> + byte |= SIGNAL_RS;
> + command = byte;
> + data_block[0] = byte | enable;
> + data_block[1] = byte;
> +
> + } else if (Bits == 8) {
> + if (rw)
> + command |= SIGNAL_RW;
> + if (rs)
> + command |= SIGNAL_RS;
> +
> + data_block[0] = byte;
> + data_block[1] = enable;
> + }
>
> - drv_generic_i2c_command(command, data_block, 2);
> + drv_generic_i2c_command(command, data_block, 2, Bits);
> }
>
>
> static void drv_HD_I2C_byte(const unsigned char controller, const unsigned char data)
> {
> /* send data with RS enabled */
> - drv_HD_I2C_nibble(controller, ((data >> 4) & 0x0f) | SIGNAL_RS);
> - drv_HD_I2C_nibble(controller, (data & 0x0f) | SIGNAL_RS);
> + if (Bits == 4) {
> + drv_HD_I2C(controller, ((data >> 4) & 0x0f), 1, 0);
> + drv_HD_I2C(controller, (data & 0x0f), 1, 0);
> + } else if (Bits == 8) {
> + drv_HD_I2C(controller, data, 1, 0);
> + }
> }
>
>
> static void drv_HD_I2C_command(const unsigned char controller, const unsigned char cmd, __attribute__ ((unused))
> const unsigned long delay)
> {
> - /* send data with RS disabled */
> - drv_HD_I2C_nibble(controller, ((cmd >> 4) & 0x0f));
> - drv_HD_I2C_nibble(controller, ((cmd) & 0x0f));
> + /* send command data with RS disabled */
> + if (Bits == 4) {
> + drv_HD_I2C(controller, ((cmd >> 4) & 0x0f), 0, 0);
> + drv_HD_I2C(controller, ((cmd) & 0x0f), 0, 0);
> + } else if (Bits == 8) {
> + drv_HD_I2C(controller, cmd, 0, 0);
> + }
> }
>
> static void drv_HD_I2C_data(const unsigned char controller, const char *string, const int len, __attribute__ ((unused))
> @@ -781,13 +804,14 @@ static int drv_HD_I2C_load(const char *section)
> {
> if (cfg_number(section, "Bits", 8, 4, 8, &Bits) < 0)
> return -1;
> - if (Bits != 4) {
> - error("%s: bad %s.Bits '%d' from %s, should be '4'", Name, section, Bits, cfg_source());
> - return -1;
> - }
>
> info("%s: using %d bit mode", Name, Bits);
>
> + if (Bits != 4 && Bits != 8) {
> + error("%s: bad %s.Bits '%d' from %s, should be '4' or '8'", Name, section, Bits, cfg_source());
> + return -1;
> + }
> +
> if (drv_generic_i2c_open(section, Name) != 0) {
> error("%s: could not initialize i2c attached device!", Name);
> return -1;
> @@ -804,16 +828,24 @@ static int drv_HD_I2C_load(const char *section)
> if ((SIGNAL_GPO = drv_generic_i2c_wire("GPO", "GND")) == 0xff)
> return -1;
>
> - /* initialize display */
> - drv_HD_I2C_nibble(allControllers, 0x03);
> - udelay(T_INIT1); /* 4 Bit mode, wait 4.1 ms */
> - drv_HD_I2C_nibble(allControllers, 0x03);
> - udelay(T_INIT2); /* 4 Bit mode, wait 100 us */
> - drv_HD_I2C_nibble(allControllers, 0x03);
> - udelay(T_INIT1); /* 4 Bit mode, wait 4.1 ms */
> - drv_HD_I2C_nibble(allControllers, 0x02);
> - udelay(T_INIT2); /* 4 Bit mode, wait 100 us */
> - drv_HD_I2C_command(allControllers, 0x28, T_EXEC); /* 4 Bit mode, 1/16 duty cycle, 5x8 font */
> + if (Bits == 4) {
> + /* initialize display */
> + drv_HD_I2C(allControllers, 0x02, 0, 0);
> + udelay(T_INIT1); /* 4 Bit mode, wait 4.1 ms */
> + drv_HD_I2C(allControllers, 0x03, 0, 0);
> + udelay(T_INIT2); /* 4 Bit mode, wait 100 us */
> + drv_HD_I2C(allControllers, 0x03, 0, 0);
> + udelay(T_INIT1); /* 4 Bit mode, wait 4.1 ms */
> + drv_HD_I2C(allControllers, 0x02, 0, 0);
> + udelay(T_INIT2); /* 4 Bit mode, wait 100 us */
> + drv_HD_I2C_command(allControllers, 0x28, T_EXEC); /* 4 Bit mode, 1/16 duty cycle, 5x8 font */
> + } else if (Bits == 8) {
> + drv_HD_I2C(allControllers, 0x30, 0, 0); /* 8 Bit mode, wait 4.1 ms */
> + udelay(T_INIT1); /* 8 Bit mode, wait 4.1 ms */
> + drv_HD_I2C(allControllers, 0x30, 0, 0); /* 8 Bit mode, wait 100 us */
> + udelay(T_INIT2); /* 8 Bit mode, wait 4.1 ms */
> + drv_HD_I2C_command(allControllers, 0x38, T_EXEC); /* 8 Bit mode, 1/16 duty cycle, 5x8 font */
> + }
>
> info("%s: I2C initialization done", Name);
>
> diff --git a/drv_generic_i2c.c b/drv_generic_i2c.c
> index 2170b0c..1bee16f 100644
> --- a/drv_generic_i2c.c
> +++ b/drv_generic_i2c.c
> @@ -62,7 +62,8 @@
> static char *Driver = "";
> static char *Section = "";
> static int i2c_device;
> -
> +static int ctrldev;
> +static int datadev;
>
> static void my_i2c_smbus_write_byte_data(const int device, const unsigned char val)
> {
> @@ -91,34 +92,49 @@ static void my_i2c_smbus_read_byte_data(const int device, const unsigned char da
> }
> #endif
>
> +int drv_generic_i2c_pre_write(int dev) {
> +
> + info("%s: selecting slave device 0x%x", Driver, dev);
> + if (ioctl(i2c_device, I2C_SLAVE, dev) < 0) {
> + error("%s: error selecting slave device 0x%x\n", Driver, dev);
> + return -EPIPE;
> + }
> +
> + info("%s: initializing I2C slave device 0x%x for output", Driver, dev);
> + if (i2c_smbus_write_byte_data(i2c_device, 3, 0) < 0) {
> + error("%s: error initializing device 0x%x\n", Driver, dev);
> + close(i2c_device);
> + }
> +
> + return 0;
> +}
>
> int drv_generic_i2c_open(const char *section, const char *driver)
> {
> - int dev;
> char *bus, *device;
> udelay_init();
> Section = (char *) section;
> Driver = (char *) driver;
> bus = cfg_get(Section, "Port", NULL);
> device = cfg_get(Section, "Device", NULL);
> - dev = atoi(device);
> + ctrldev = atoi(device);
> + device = cfg_get(Section, "DDevice", NULL);
> + datadev = atoi(device);
> +
> info("%s: initializing I2C bus %s", Driver, bus);
> if ((i2c_device = open(bus, O_WRONLY)) < 0) {
> error("%s: I2C bus %s open failed !\n", Driver, bus);
> goto exit_error;
> }
> - info("%s: selecting slave device 0x%x", Driver, dev);
> - if (ioctl(i2c_device, I2C_SLAVE, dev) < 0) {
> - error("%s: error selecting slave device 0x%x\n", Driver, dev);
> - goto exit_error;
> - }
>
> - info("%s: initializing I2C slave device 0x%x", Driver, dev);
> - if (i2c_smbus_write_quick(i2c_device, I2C_SMBUS_WRITE) < 0) {
> - error("%s: error initializing device 0x%x\n", Driver, dev);
> - close(i2c_device);
> + if (datadev) {
> + if (drv_generic_i2c_pre_write(datadev) < 0)
> + goto exit_error;
> }
>
> + if (drv_generic_i2c_pre_write(ctrldev) < 0)
> + goto exit_error;
> +
> return 0;
>
> exit_error:
> @@ -172,8 +188,29 @@ void drv_generic_i2c_data(const unsigned char data)
> my_i2c_smbus_write_byte_data(i2c_device, data);
> }
>
> +static void i2c_out(int dev, unsigned char val)
> +{
> + info("%s: initializing I2C slave device 0x%x", Driver, dev);
> + if (ioctl(i2c_device, I2C_SLAVE, dev) < 0) {
> + error("%s: error selecting slave device 0x%x\n", Driver, dev);
> + return;
> + }
> +
> + i2c_smbus_write_byte_data(i2c_device, 1, val);
> +}
>
> -void drv_generic_i2c_command(const unsigned char command, /*const */ unsigned char *data, const unsigned char length)
> +void drv_generic_i2c_command(const unsigned char command, /*const */ unsigned char *data, const unsigned char length, int bits)
> {
> - i2c_smbus_write_block_data(i2c_device, command, length, data);
> + if (bits == 4) {
> + i2c_smbus_write_block_data(i2c_device, command, length, data);
> + } else if (bits == 8 && datadev) {
> + /* set data on pins */
> + info("cmd: %08x, data0: %08x, data1: %08x\n", command, data[0], data[1]);
> + i2c_out(datadev, data[0]);
> + /* set enable pin including optional rs and rw */
> + i2c_out(ctrldev, command | data[1]);
> + /* unset enable pin including optional rs and rw */
> + i2c_out(ctrldev, command);
> + }
> +
> }
> diff --git a/drv_generic_i2c.h b/drv_generic_i2c.h
> index 2cc6a02..bd68e44 100644
> --- a/drv_generic_i2c.h
> +++ b/drv_generic_i2c.h
> @@ -57,6 +57,6 @@ int drv_generic_i2c_close(void);
> unsigned char drv_generic_i2c_wire(const char *name, const char *deflt);
> void drv_generic_i2c_byte(const unsigned char data);
> void drv_generic_i2c_data(const unsigned char data);
> -void drv_generic_i2c_command(const unsigned char command, /*const */ unsigned char *data, const unsigned char length);
> +void drv_generic_i2c_command(const unsigned char command, /*const */ unsigned char *data, const unsigned char length, int bits);
>
> #endif
>
--
Michael Reinelt <mi...@re...>
http://home.pages.at/reinelt
GPG-Key 0xDF13BA50
ICQ #288386781
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