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phy: phy-mtk-tphy: add configurable parameters for slew rate calibrate

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There are two parameters, ref_clk and coefficient, for U2 slew rate
calibrate which may vary on different SoCs, here allow them to be
configurable

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
This commit is contained in:
Chunfeng Yun 2018-03-12 13:25:39 +08:00 committed by Kishon Vijay Abraham I
parent 4036325609
commit 8833ebf4f8
1 changed files with 15 additions and 5 deletions
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20
drivers/phy/mediatek/phy-mtk-tphy.c
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@ -306,6 +306,8 @@ struct mtk_tphy {
const struct mtk_phy_pdata *pdata;
struct mtk_phy_instance **phys;
int nphys;
int src_ref_clk; /* MHZ, reference clock for slew rate calibrate */
int src_coef; /* coefficient for slew rate calibrate */
};
static void hs_slew_rate_calibrate(struct mtk_tphy *tphy,
@ -360,16 +362,17 @@ static void hs_slew_rate_calibrate(struct mtk_tphy *tphy,
writel(tmp, fmreg + U3P_U2FREQ_FMMONR1);
if (fm_out) {
/* ( 1024 / FM_OUT ) x reference clock frequency x 0.028 */
tmp = U3P_FM_DET_CYCLE_CNT * U3P_REF_CLK * U3P_SLEW_RATE_COEF;
tmp /= fm_out;
/* ( 1024 / FM_OUT ) x reference clock frequency x coef */
tmp = tphy->src_ref_clk * tphy->src_coef;
tmp = (tmp * U3P_FM_DET_CYCLE_CNT) / fm_out;
calibration_val = DIV_ROUND_CLOSEST(tmp, U3P_SR_COEF_DIVISOR);
} else {
/* if FM detection fail, set default value */
calibration_val = 4;
}
dev_dbg(tphy->dev, "phy:%d, fm_out:%d, calib:%d\n",
instance->index, fm_out, calibration_val);
dev_dbg(tphy->dev, "phy:%d, fm_out:%d, calib:%d (clk:%d, coef:%d)\n",
instance->index, fm_out, calibration_val,
tphy->src_ref_clk, tphy->src_coef);
/* set HS slew rate */
tmp = readl(com + U3P_USBPHYACR5);
@ -1041,6 +1044,13 @@ static int mtk_tphy_probe(struct platform_device *pdev)
tphy->u3phya_ref = NULL;
}
tphy->src_ref_clk = U3P_REF_CLK;
tphy->src_coef = U3P_SLEW_RATE_COEF;
/* update parameters of slew rate calibrate if exist */
device_property_read_u32(dev, "mediatek,src-ref-clk-mhz",
&tphy->src_ref_clk);
device_property_read_u32(dev, "mediatek,src-coef", &tphy->src_coef);
port = 0;
for_each_child_of_node(np, child_np) {
struct mtk_phy_instance *instance;