Re: [PATCH v4] i2c: designware: Enable SAR in slave mode for Multiple SAR controllers
Andy Shevchenko <[email protected]>
| Newsgroups | org.kernel.vger.linux-i2c,org.kernel.vger.linux-kernel |
|---|---|
| Organization | Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo |
| Message-ID | <[email protected]> |
On Mon, Aug 17, 2026 at 02:10:23PM +0530, Umesh Kumar wrote: > DesignWare controllers synthesised with the Multiple SAR feature (e.g. > Marvell CN20K) gate the primary slave address behind IC_ENABLE.SAR_EN > (bit 19). Per the Synopsys DW_apb_i2c DataBook v2.03a (Multiple SAR > feature),when this bit is set the core acknowledges the address matching Missing space after ). > IC_SAR;otherwise the address is NACKed. The slave enable path writes only Same here for ;. > IC_ENABLE.ENABLE (bit 0), so on such controllers the target never ACKs > its address and a remote master cannot reach it. > > Set SAR_EN together with ENABLE when entering slave mode. The bit is > reserved (and ignored) on single-SAR controllers, so existing users are > unaffected. Reviewed-by: Andy Shevchenko <[email protected]> -- With Best Regards, Andy Shevchenko