Re: [PATCH i2c-tools] i2cget: Add support for i2c block data

[Guenter Roeck <linux@roeck-us.net>]

On 05/13/2016 11:54 AM, Crestez Dan Leonard wrote:
> This adds mode 'i' for I2C_SMBUS_I2C_BLOCK_DATA. This is the same mode
> letter from i2cdump.
>
> Length is optional and defaults to 32 (maximum).
>
> The indended use is debugging i2c devices with shell commands.
>
How does this differ from the 'i' option of i2cdump ?

Guenter

> Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
> ---
> I'm not sure this is where patches for i2c-tools should be sent. This patch is
> on top of latest master from https://github.com/groeck/i2c-tools
>
> The README claims the latest version can be downloaded from www.lm-sensors.org
> but that seems to have been down for a while.
>
>   tools/i2cget.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++----------
>   1 file changed, 51 insertions(+), 10 deletions(-)
>
> diff --git a/tools/i2cget.c b/tools/i2cget.c
> index 2503942..5d8dfe7 100644
> --- a/tools/i2cget.c
> +++ b/tools/i2cget.c
> @@ -41,14 +41,16 @@ static void help(void) __attribute__ ((noreturn));
>   static void help(void)
>   {
>   	fprintf(stderr,
> -		"Usage: i2cget [-f] [-y] I2CBUS CHIP-ADDRESS [DATA-ADDRESS [MODE]]\n"
> +		"Usage: i2cget [-f] [-y] I2CBUS CHIP-ADDRESS [DATA-ADDRESS [MODE] [LENGTH]]\n"
>   		"  I2CBUS is an integer or an I2C bus name\n"
>   		"  ADDRESS is an integer (0x03 - 0x77)\n"
>   		"  MODE is one of:\n"
>   		"    b (read byte data, default)\n"
>   		"    w (read word data)\n"
>   		"    c (write byte/read byte)\n"
> -		"    Append p for SMBus PEC\n");
> +		"    i (read I2C block data)\n"
> +		"    Append p for SMBus PEC\n"
> +		"  LENGTH is length for block data reads\n");
>   	exit(1);
>   }
>
> @@ -89,6 +91,13 @@ static int check_funcs(int file, int size, int daddress, int pec)
>   			return -1;
>   		}
>   		break;
> +
> +	case I2C_SMBUS_I2C_BLOCK_DATA:
> +		if (!(funcs & I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
> +			fprintf(stderr, MISSING_FUNC_FMT, "SMBus read I2C block data");
> +			return -1;
> +		}
> +		break;
>   	}
>
>   	if (pec
> @@ -101,7 +110,7 @@ static int check_funcs(int file, int size, int daddress, int pec)
>   }
>
>   static int confirm(const char *filename, int address, int size, int daddress,
> -		   int pec)
> +		   int length, int pec)
>   {
>   	int dont = 0;
>
> @@ -132,11 +141,14 @@ static int confirm(const char *filename, int address, int size, int daddress,
>   		fprintf(stderr, "current data\naddress");
>   	else
>   		fprintf(stderr, "data address\n0x%02x", daddress);
> -	fprintf(stderr, ", using %s.\n",
> -		size == I2C_SMBUS_BYTE ? (daddress < 0 ?
> -		"read byte" : "write byte/read byte") :
> -		size == I2C_SMBUS_BYTE_DATA ? "read byte data" :
> -		"read word data");
> +        if (size == I2C_SMBUS_I2C_BLOCK_DATA)
> +            fprintf(stderr, ", %d bytes using read I2C block data.\n", bytes);
> +        else
> +            fprintf(stderr, ", using %s.\n",
> +                    size == I2C_SMBUS_BYTE ? (daddress < 0 ?
> +                    "read byte" : "write byte/read byte") :
> +                    size == I2C_SMBUS_BYTE_DATA ? "read byte data" :
> +                    "read word data");
>   	if (pec)
>   		fprintf(stderr, "PEC checking enabled.\n");
>
> @@ -159,6 +171,8 @@ int main(int argc, char *argv[])
>   	int pec = 0;
>   	int flags = 0;
>   	int force = 0, yes = 0, version = 0;
> +	int length;
> +	__u8 block_data[I2C_SMBUS_BLOCK_MAX];
>
>   	/* handle (optional) flags first */
>   	while (1+flags < argc && argv[1+flags][0] == '-') {
> @@ -208,6 +222,7 @@ int main(int argc, char *argv[])
>   		case 'b': size = I2C_SMBUS_BYTE_DATA; break;
>   		case 'w': size = I2C_SMBUS_WORD_DATA; break;
>   		case 'c': size = I2C_SMBUS_BYTE; break;
> +		case 'i': size = I2C_SMBUS_I2C_BLOCK_DATA; break;
>   		default:
>   			fprintf(stderr, "Error: Invalid mode!\n");
>   			help();
> @@ -215,13 +230,27 @@ int main(int argc, char *argv[])
>   		pec = argv[flags+4][1] == 'p';
>   	}
>
> +	if (argc > flags + 5) {
> +		if (size != I2C_SMBUS_I2C_BLOCK_DATA) {
> +			fprintf(stderr, "Error: Length only valid for I2C block data!\n");
> +			help();
> +		}
> +		length = strtol(argv[flags+5], &end, 0);
> +		if (*end || length < 1 || length > I2C_SMBUS_BLOCK_MAX) {
> +			fprintf(stderr, "Error: Length invalid!\n");
> +			help();
> +		}
> +	} else {
> +		length = I2C_SMBUS_BLOCK_MAX;
> +	}
> +
>   	file = open_i2c_dev(i2cbus, filename, sizeof(filename), 0);
>   	if (file < 0
>   	 || check_funcs(file, size, daddress, pec)
>   	 || set_slave_addr(file, address, force))
>   		exit(1);
>
> -	if (!yes && !confirm(filename, address, size, daddress, pec))
> +	if (!yes && !confirm(filename, address, size, daddress, length, pec))
>   		exit(0);
>
>   	if (pec && ioctl(file, I2C_PEC, 1) < 0) {
> @@ -243,6 +272,9 @@ int main(int argc, char *argv[])
>   	case I2C_SMBUS_WORD_DATA:
>   		res = i2c_smbus_read_word_data(file, daddress);
>   		break;
> +	case I2C_SMBUS_I2C_BLOCK_DATA:
> +		res = i2c_smbus_read_i2c_block_data(file, daddress, length, block_data);
> +		break;
>   	default: /* I2C_SMBUS_BYTE_DATA */
>   		res = i2c_smbus_read_byte_data(file, daddress);
>   	}
> @@ -253,7 +285,16 @@ int main(int argc, char *argv[])
>   		exit(2);
>   	}
>
> -	printf("0x%0*x\n", size == I2C_SMBUS_WORD_DATA ? 4 : 2, res);
> +	if (size == I2C_SMBUS_I2C_BLOCK_DATA) {
> +		int i;
> +                printf("%d:", res);
> +		for (i = 0; i < res; ++i) {
> +			printf(" 0x%02hhx", block_data[i]);
> +		}
> +		printf("\n");
> +	} else {
> +		printf("0x%0*x\n", size == I2C_SMBUS_WORD_DATA ? 4 : 2, res);
> +	}
>
>   	exit(0);
>   }
>