From c4313e75001492f8a288d3ffd595544cbc880821 Mon Sep 17 00:00:00 2001 From: Peter Geis Date: Sat, 5 Mar 2022 16:58:34 -0500 Subject: [PATCH] mmc: dw_mmc: Support setting f_min from host drivers Host drivers may not be able to support frequencies as low as dw-mmc supports. Unfortunately f_min isn't available when the drv_data->init function is called, as the mmc_host struct hasn't been set up yet. Support the host drivers saving the requested minimum frequency, so we can later set f_min when it is available. Signed-off-by: Peter Geis Link: https://lore.kernel.org/r/20220305215835.2210388-2-pgwipeout@gmail.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/dw_mmc.c | 7 ++++++- drivers/mmc/host/dw_mmc.h | 2 ++ 2 files changed, 8 insertions(+), 1 deletion(-) --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -2853,7 +2853,12 @@ static int dw_mci_init_slot_caps(struct if (host->pdata->caps2) mmc->caps2 = host->pdata->caps2; - mmc->f_min = DW_MCI_FREQ_MIN; + /* if host has set a minimum_freq, we should respect it */ + if (host->minimum_speed) + mmc->f_min = host->minimum_speed; + else + mmc->f_min = DW_MCI_FREQ_MIN; + if (!mmc->f_max) mmc->f_max = DW_MCI_FREQ_MAX; --- a/drivers/mmc/host/dw_mmc.h +++ b/drivers/mmc/host/dw_mmc.h @@ -99,6 +99,7 @@ struct dw_mci_dma_slave { * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus * rate and timeout calculations. * @current_speed: Configured rate of the controller. + * @minimum_speed: Stored minimum rate of the controller. * @fifoth_val: The value of FIFOTH register. * @verid: Denote Version ID. * @dev: Device associated with the MMC controller. @@ -200,6 +201,7 @@ struct dw_mci { u32 bus_hz; u32 current_speed; + u32 minimum_speed; u32 fifoth_val; u16 verid; struct device *dev;