On 10/30/23 12:40, Pierre-Louis Bossart wrote:
On 10/30/23 12:20, Mark Brown wrote:
On Mon, Oct 30, 2023 at 11:05:39AM -0500, Pierre-Louis Bossart wrote:
+static bool tas2783_readable_register(struct device *dev, unsigned int reg) +{
- switch (reg) {
- case 0x000 ... 0x080: /* Data port 0. */
No, this is wrong. All the data port 'standard' registers are "owned" by the SoundWire core and handled during the port prepare/configure/bank switch routines. Do not use them for regmap.
In other words, you *shall* only define vendor-specific registers in this codec driver.
This seems to come up a moderate amount and is an understandable thing to do - could you (or someone else who knows SoundWire) perhaps send a patch for the regmap SoundWire integration which does some validation here during registration and at least prints a warning?
Good suggestion, we could indeed check that the registers are NOT in the range [0,0xBF] for all ports - only the range [0xC0..FF] is allowed for implementation-defined values. I'll try to cook something up.
After checking, the following ranges are invalid for codec drivers:
for address < 0x1000 LSB = 0x00 - 0xBF standard or reserved
0x1800 – 0x1FFF reserved 0x48000000 - 0xFFFFFFFF reserved
is the recommendation to check the regmap_config and its 'yes_ranges'?
Presumably if the range_min or range_max is within the invalid values above then the configuration can be tagged as problematic in the dmesg log or rejected with an error code?