[PATCH v7 04/18] spi: spi-mem: teach spi_mem_adjust_op_freq() about post-config ops

[Santhosh Kumar K <s-k6@ti.com>]

Extend spi_mem_adjust_op_freq() with a bypass for post-config ops:
when op->max_freq equals post_config_max_speed_hz (the value written by
execute_tuning on success), return immediately leaving op->max_freq
unchanged. All other ops are capped to max_speed_hz, the
always-reachable base rate. This places the policy at the single
existing frequency-adjustment point so exec_op(), supports_op(), and
calc_op_duration() all see consistent frequencies.

Also extend spi_mem_default_supports_op() to require per_op_freq
controller capability for post-config ops. A post-config op runs at a
different clock rate than the pre-config base; a controller that cannot
switch frequencies per-op cannot execute it correctly.

Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Santhosh Kumar K <s-k6@ti.com>
---
 drivers/spi/spi-mem.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index a88b9f038356..c74858e58073 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -206,7 +206,8 @@ bool spi_mem_default_supports_op(struct spi_mem *mem,
 		return false;
 
 	if (op->max_freq &&
-	    op->max_freq < mem->spi->max_speed_hz) {
+	    (op->max_freq < mem->spi->max_speed_hz ||
+	     op->max_freq == mem->spi->post_config_max_speed_hz)) {
 		if (!spi_mem_controller_is_capable(ctlr, per_op_freq))
 			return false;
 	}
@@ -591,9 +592,18 @@ EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
  * Some chips have per-op frequency limitations and must adapt the maximum
  * speed. This function allows SPI mem drivers to set @op->max_freq to the
  * maximum supported value.
+ *
+ * When @mem->spi->post_config_max_speed_hz is set, ops with @op->max_freq
+ * equal to that value are treated as post-configuration ops (e.g. PHY-tuned)
+ * and are allowed to run at the full post-config rate. All other ops are
+ * capped to @mem->spi->max_speed_hz, the always-reachable base rate.
  */
 void spi_mem_adjust_op_freq(struct spi_mem *mem, struct spi_mem_op *op)
 {
+	if (mem->spi->post_config_max_speed_hz &&
+	    op->max_freq == mem->spi->post_config_max_speed_hz)
+		return;
+
 	if (!op->max_freq || op->max_freq > mem->spi->max_speed_hz)
 		op->max_freq = mem->spi->max_speed_hz;
 }
-- 
2.34.1