spi: sh-msiof: Fill in controller speed limits

Fill in the controller speed limits, so the SPI core can use them for
validating SPI transfers, and adjust or reject transfers when needed.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20210113101916.1147695-3-geert+renesas@glider.beSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-sh-msiof.c

@@ -1262,6 +1262,7 @@ static int sh_msiof_spi_probe(struct platform_device *pdev)
 	const struct sh_msiof_chipdata *chipdata;
 	struct sh_msiof_spi_info *info;
 	struct sh_msiof_spi_priv *p;
+	unsigned long clksrc;
 	int i;
 	int ret;
 
@@ -1337,6 +1338,9 @@ static int sh_msiof_spi_probe(struct platform_device *pdev)
 	/* init controller code */
 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 	ctlr->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
+	clksrc = clk_get_rate(p->clk);
+	ctlr->min_speed_hz = DIV_ROUND_UP(clksrc, 1024);
+	ctlr->max_speed_hz = DIV_ROUND_UP(clksrc, 1 << p->min_div_pow);
 	ctlr->flags = chipdata->ctlr_flags;
 	ctlr->bus_num = pdev->id;
 	ctlr->num_chipselect = p->info->num_chipselect;