mirror of https://gitee.com/openkylin/linux.git
4b2643d7d9
Let the drivers specify how many bytes they want to read with i2c_smbus_read_i2c_block_data(). So far, the block count was hard-coded to I2C_SMBUS_BLOCK_MAX (32), which did not make much sense. Many driver authors complained about this before, and I believe it's about time to fix it. Right now, authors have to do technically stupid things, such as individual byte reads or full-fledged I2C messaging, to work around the problem. We do not want to encourage that. I even found that some bus drivers (e.g. i2c-amd8111) already implemented I2C block read the "right" way, that is, they didn't follow the old, broken standard. The fact that it was never noticed before just shows how little i2c_smbus_read_i2c_block_data() was used, which isn't that surprising given how broken its prototype was so far. There are some obvious compatiblity considerations: * This changes the i2c_smbus_read_i2c_block_data() prototype. Users outside the kernel tree will notice at compilation time, and will have to update their code. * User-space has access to i2c_smbus_xfer() directly using i2c-dev, so the changed expectations would affect tools such as i2cdump. In order to preserve binary compatibility, we give I2C_SMBUS_I2C_BLOCK_DATA a new numeric value, and define I2C_SMBUS_I2C_BLOCK_BROKEN with the old numeric value. When i2c-dev receives a transaction with the old value, it can convert it to the new format on the fly. Signed-off-by: Jean Delvare <khali@linux-fr.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| i2c-acorn.c | ||
| i2c-ali15x3.c | ||
| i2c-ali1535.c | ||
| i2c-ali1563.c | ||
| i2c-amd756-s4882.c | ||
| i2c-amd756.c | ||
| i2c-amd8111.c | ||
| i2c-at91.c | ||
| i2c-au1550.c | ||
| i2c-au1550.h | ||
| i2c-bfin-twi.c | ||
| i2c-elektor.c | ||
| i2c-gpio.c | ||
| i2c-hydra.c | ||
| i2c-i801.c | ||
| i2c-i810.c | ||
| i2c-ibm_iic.c | ||
| i2c-ibm_iic.h | ||
| i2c-iop3xx.c | ||
| i2c-iop3xx.h | ||
| i2c-isa.c | ||
| i2c-ixp4xx.c | ||
| i2c-ixp2000.c | ||
| i2c-mpc.c | ||
| i2c-mv64xxx.c | ||
| i2c-nforce2.c | ||
| i2c-ocores.c | ||
| i2c-omap.c | ||
| i2c-parport-light.c | ||
| i2c-parport.c | ||
| i2c-parport.h | ||
| i2c-pasemi.c | ||
| i2c-pca-isa.c | ||
| i2c-piix4.c | ||
| i2c-pnx.c | ||
| i2c-powermac.c | ||
| i2c-prosavage.c | ||
| i2c-pxa.c | ||
| i2c-rpx.c | ||
| i2c-s3c2410.c | ||
| i2c-savage4.c | ||
| i2c-sibyte.c | ||
| i2c-simtec.c | ||
| i2c-sis96x.c | ||
| i2c-sis630.c | ||
| i2c-sis5595.c | ||
| i2c-stub.c | ||
| i2c-tiny-usb.c | ||
| i2c-versatile.c | ||
| i2c-via.c | ||
| i2c-viapro.c | ||
| i2c-voodoo3.c | ||
| scx200_acb.c | ||
| scx200_i2c.c | ||