Quoting Douglas Anderson (2020-10-08 15:52:35)
> diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
> index 751a49f6534f..746854745b15 100644
> --- a/drivers/soc/qcom/qcom-geni-se.c
> +++ b/drivers/soc/qcom/qcom-geni-se.c
> @@ -266,49 +266,53 @@ EXPORT_SYMBOL(geni_se_init);
> static void geni_se_select_fifo_mode(struct geni_se *se)
> {
> u32 proto = geni_se_read_proto(se);
> - u32 val;
> + u32 val, val_old;
>
> geni_se_irq_clear(se);
>
> - val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
> if (proto != GENI_SE_UART) {
> + val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
> val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
> val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
> - }
> - writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
> + if (val != val_old)
> + writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
>
> - val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
> - if (proto != GENI_SE_UART)
> - val |= S_CMD_DONE_EN;
> - writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
> + val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
Can we use the val_old trick here too?
> + if (!(val & S_CMD_DONE_EN))
> + writel_relaxed(val | S_CMD_DONE_EN,
Because this val | S_CMD_DONE_EN thing is just hard to read :/
> + se->base + SE_GENI_S_IRQ_EN);
> + }
>
> val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
> - val &= ~GENI_DMA_MODE_EN;
> - writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
> + if (val & GENI_DMA_MODE_EN)
> + writel_relaxed(val & ~GENI_DMA_MODE_EN,
> + se->base + SE_GENI_DMA_MODE_EN);
> }
>
