Re: [PATCH v2] w1:fix byteorder of W1_READ_ROM id under big-endian cpu
Hi 28.08.2017, 12:25, "chen.l...@zte.com.cn": > Hi > > Q: > > But w1_reg_num has a different layout for be/le systems, isn't it enough? > > A: > > sure, it's right only under the assumption that 'rn' is a correct layout id. > > Here's my example in be system which I encounter before. > > buf[0] return from w1_read_8(dev) in code section2 will always be 'family:8', > buf[0] store at the first byte of rn, then it will be transport to cb(dev, > rn) in code section1, > > but it will be parsed to 'crc:8' of the struct w1_reg_num in be system, then > there comes the wrong. Sorry, I do not understand. Do you mean that there is a difference between 2 ways to read ID content in w1_read_block() ? If it is the case, is it possible, that there is a bug in particular master implementation? There is a fair number of be devices in the tree already, and no one yet reported that there is an endian issue.
Re: [PATCH v2] w1:fix byteorder of W1_READ_ROM id under big-endian cpu
Hi 28.08.2017, 12:25, "chen.l...@zte.com.cn" : > Hi > > Q: > > But w1_reg_num has a different layout for be/le systems, isn't it enough? > > A: > > sure, it's right only under the assumption that 'rn' is a correct layout id. > > Here's my example in be system which I encounter before. > > buf[0] return from w1_read_8(dev) in code section2 will always be 'family:8', > buf[0] store at the first byte of rn, then it will be transport to cb(dev, > rn) in code section1, > > but it will be parsed to 'crc:8' of the struct w1_reg_num in be system, then > there comes the wrong. Sorry, I do not understand. Do you mean that there is a difference between 2 ways to read ID content in w1_read_block() ? If it is the case, is it possible, that there is a bug in particular master implementation? There is a fair number of be devices in the tree already, and no one yet reported that there is an endian issue.
Re: [PATCH v2] w1:fix byteorder of W1_READ_ROM id under big-endian cpu
Hi Chen 19.07.2017, 10:58, "Chen Lin": > The byteorder of para rn(W1_READ_ROM id) pass to w1_slave_found must > be the same with the byterorder defined in struct w1_reg_num. > > The rn read from 'rv = w1_read_block(dev, (u8 *), 8)' is a byte > serial and not cpu endian relative, it need to change to cpu endian > before passed to w1_slave_found. But w1_reg_num has a different layout for be/le systems, isn't it enough? > Signed-off-by: Chen Lin > Reviewed-by: Jiang Biao > --- > Forgot the description in v1. > > --- > drivers/w1/w1.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c > index 95ea7e6..c531545 100644 > --- a/drivers/w1/w1.c > +++ b/drivers/w1/w1.c > @@ -979,7 +979,7 @@ void w1_search(struct w1_master *dev, u8 search_type, > w1_slave_found_callback cb > mutex_unlock(>bus_mutex); > > if (rv == 8 && rn) > - cb(dev, rn); > + cb(dev, le64_to_cpu(rn)); > > break; > } > -- > 1.8.3.1
Re: [PATCH v2] w1:fix byteorder of W1_READ_ROM id under big-endian cpu
Hi Chen 19.07.2017, 10:58, "Chen Lin" : > The byteorder of para rn(W1_READ_ROM id) pass to w1_slave_found must > be the same with the byterorder defined in struct w1_reg_num. > > The rn read from 'rv = w1_read_block(dev, (u8 *), 8)' is a byte > serial and not cpu endian relative, it need to change to cpu endian > before passed to w1_slave_found. But w1_reg_num has a different layout for be/le systems, isn't it enough? > Signed-off-by: Chen Lin > Reviewed-by: Jiang Biao > --- > Forgot the description in v1. > > --- > drivers/w1/w1.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c > index 95ea7e6..c531545 100644 > --- a/drivers/w1/w1.c > +++ b/drivers/w1/w1.c > @@ -979,7 +979,7 @@ void w1_search(struct w1_master *dev, u8 search_type, > w1_slave_found_callback cb > mutex_unlock(>bus_mutex); > > if (rv == 8 && rn) > - cb(dev, rn); > + cb(dev, le64_to_cpu(rn)); > > break; > } > -- > 1.8.3.1
[PATCH v2] w1:fix byteorder of W1_READ_ROM id under big-endian cpu
The byteorder of para rn(W1_READ_ROM id) pass to w1_slave_found must be the same with the byterorder defined in struct w1_reg_num. The rn read from 'rv = w1_read_block(dev, (u8 *), 8)' is a byte serial and not cpu endian relative, it need to change to cpu endian before passed to w1_slave_found. Signed-off-by: Chen LinReviewed-by: Jiang Biao --- Forgot the description in v1. --- drivers/w1/w1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 95ea7e6..c531545 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -979,7 +979,7 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb mutex_unlock(>bus_mutex); if (rv == 8 && rn) - cb(dev, rn); + cb(dev, le64_to_cpu(rn)); break; } -- 1.8.3.1
[PATCH v2] w1:fix byteorder of W1_READ_ROM id under big-endian cpu
The byteorder of para rn(W1_READ_ROM id) pass to w1_slave_found must be the same with the byterorder defined in struct w1_reg_num. The rn read from 'rv = w1_read_block(dev, (u8 *), 8)' is a byte serial and not cpu endian relative, it need to change to cpu endian before passed to w1_slave_found. Signed-off-by: Chen Lin Reviewed-by: Jiang Biao --- Forgot the description in v1. --- drivers/w1/w1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 95ea7e6..c531545 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -979,7 +979,7 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb mutex_unlock(>bus_mutex); if (rv == 8 && rn) - cb(dev, rn); + cb(dev, le64_to_cpu(rn)); break; } -- 1.8.3.1