diff options
| author | Damien George <damien@micropython.org> | 2022-06-17 11:57:57 +1000 |
|---|---|---|
| committer | Damien George <damien@micropython.org> | 2022-06-17 11:57:57 +1000 |
| commit | 5233fb3a3d3245bd4c5dfb781e3fcbc8a3fbfd6a (patch) | |
| tree | d688042af2db862d0cf9b11256f5d051208adecf /extmod/machine_i2c.c | |
| parent | d7919ea71e7b7cc203ca984cc2f4a55019634835 (diff) | |
extmod/machine_i2c: Only use WRITE1 option if transfer supports it.
When MICROPY_PY_MACHINE_I2C_TRANSFER_WRITE1 is enabled the port's hardware
I2C transfer functions should support the MP_MACHINE_I2C_FLAG_WRITE1
option, but software I2C will not. So add a flag to the I2C protocol
struct so each individual protocol can indicate whether it supports this
option or not.
Fixes issue #8765.
Signed-off-by: Damien George <damien@micropython.org>
Diffstat (limited to 'extmod/machine_i2c.c')
| -rw-r--r-- | extmod/machine_i2c.c | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/extmod/machine_i2c.c b/extmod/machine_i2c.c index 7d0628a2d..452f07a2e 100644 --- a/extmod/machine_i2c.c +++ b/extmod/machine_i2c.c @@ -515,19 +515,20 @@ STATIC int read_mem(mp_obj_t self_in, uint16_t addr, uint32_t memaddr, uint8_t a size_t memaddr_len = fill_memaddr_buf(&memaddr_buf[0], memaddr, addrsize); #if MICROPY_PY_MACHINE_I2C_TRANSFER_WRITE1 - - // Create partial write and read buffers - mp_machine_i2c_buf_t bufs[2] = { - {.len = memaddr_len, .buf = memaddr_buf}, - {.len = len, .buf = buf}, - }; - - // Do write+read I2C transfer + // The I2C transfer function may support the MP_MACHINE_I2C_FLAG_WRITE1 option mp_machine_i2c_p_t *i2c_p = (mp_machine_i2c_p_t *)self->type->protocol; - return i2c_p->transfer(self, addr, 2, bufs, - MP_MACHINE_I2C_FLAG_WRITE1 | MP_MACHINE_I2C_FLAG_READ | MP_MACHINE_I2C_FLAG_STOP); + if (i2c_p->transfer_supports_write1) { + // Create partial write and read buffers + mp_machine_i2c_buf_t bufs[2] = { + {.len = memaddr_len, .buf = memaddr_buf}, + {.len = len, .buf = buf}, + }; - #else + // Do write+read I2C transfer + return i2c_p->transfer(self, addr, 2, bufs, + MP_MACHINE_I2C_FLAG_WRITE1 | MP_MACHINE_I2C_FLAG_READ | MP_MACHINE_I2C_FLAG_STOP); + } + #endif int ret = mp_machine_i2c_writeto(self, addr, memaddr_buf, memaddr_len, false); if (ret != memaddr_len) { @@ -536,8 +537,6 @@ STATIC int read_mem(mp_obj_t self_in, uint16_t addr, uint32_t memaddr, uint8_t a return ret; } return mp_machine_i2c_readfrom(self, addr, buf, len, true); - - #endif } STATIC int write_mem(mp_obj_t self_in, uint16_t addr, uint32_t memaddr, uint8_t addrsize, const uint8_t *buf, size_t len) { |