Commit b6e67145 authored by Weifeng Voon's avatar Weifeng Voon Committed by Wolfram Sang
Browse files

i2c: designware: Enable high speed mode



This patch enabled high speed mode. High speed mode can be turn on by
setting the clk_freq to 3400000. High speed HCNT and LCNT are needed
as there is no default value provided.

Signed-off-by: default avatarWeifeng Voon <weifeng.voon@intel.com>
Signed-off-by: default avatarJarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 548e6695
......@@ -42,6 +42,8 @@
#define DW_IC_SS_SCL_LCNT 0x18
#define DW_IC_FS_SCL_HCNT 0x1c
#define DW_IC_FS_SCL_LCNT 0x20
#define DW_IC_HS_SCL_HCNT 0x24
#define DW_IC_HS_SCL_LCNT 0x28
#define DW_IC_INTR_STAT 0x2c
#define DW_IC_INTR_MASK 0x30
#define DW_IC_RAW_INTR_STAT 0x34
......@@ -95,6 +97,9 @@
#define DW_IC_TAR_10BITADDR_MASTER BIT(12)
#define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH (BIT(2) | BIT(3))
#define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK GENMASK(3, 2)
/*
* status codes
*/
......@@ -293,7 +298,7 @@ static unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev)
int i2c_dw_init(struct dw_i2c_dev *dev)
{
u32 hcnt, lcnt;
u32 reg;
u32 reg, comp_param1;
u32 sda_falling_time, scl_falling_time;
int ret;
......@@ -320,6 +325,8 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
return -ENODEV;
}
comp_param1 = dw_readl(dev, DW_IC_COMP_PARAM_1);
/* Disable the adapter */
__i2c_dw_enable(dev, false);
......@@ -369,6 +376,23 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT);
dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
if ((dev->master_cfg & DW_IC_CON_SPEED_MASK) ==
DW_IC_CON_SPEED_HIGH) {
if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK)
!= DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH) {
dev_err(dev->dev, "High Speed not supported!\n");
dev->master_cfg &= ~DW_IC_CON_SPEED_MASK;
dev->master_cfg |= DW_IC_CON_SPEED_FAST;
} else if (dev->hs_hcnt && dev->hs_lcnt) {
hcnt = dev->hs_hcnt;
lcnt = dev->hs_lcnt;
dw_writel(dev, hcnt, DW_IC_HS_SCL_HCNT);
dw_writel(dev, lcnt, DW_IC_HS_SCL_LCNT);
dev_dbg(dev->dev, "HighSpeed-mode HCNT:LCNT = %d:%d\n",
hcnt, lcnt);
}
}
/* Configure SDA Hold Time if required */
if (dev->sda_hold_time) {
reg = dw_readl(dev, DW_IC_COMP_VERSION);
......
......@@ -26,6 +26,7 @@
#define DW_IC_CON_MASTER 0x1
#define DW_IC_CON_SPEED_STD 0x2
#define DW_IC_CON_SPEED_FAST 0x4
#define DW_IC_CON_SPEED_HIGH 0x6
#define DW_IC_CON_SPEED_MASK 0x6
#define DW_IC_CON_10BITADDR_MASTER 0x10
#define DW_IC_CON_RESTART_EN 0x20
......
......@@ -197,12 +197,12 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
/*
* Only standard mode at 100kHz, fast mode at 400kHz,
* and fast mode plus at 1MHz are supported.
* fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
*/
if (dev->clk_freq != 100000 && dev->clk_freq != 400000
&& dev->clk_freq != 1000000) {
&& dev->clk_freq != 1000000 && dev->clk_freq != 3400000) {
dev_err(&pdev->dev,
"Only 100kHz, 400kHz and 1MHz are supported");
"Only 100kHz, 400kHz, 1MHz and 3.4MHz supported");
return -EINVAL;
}
......@@ -221,10 +221,16 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
DW_IC_CON_RESTART_EN;
if (dev->clk_freq == 100000)
switch (dev->clk_freq) {
case 100000:
dev->master_cfg |= DW_IC_CON_SPEED_STD;
else
break;
case 3400000:
dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
break;
default:
dev->master_cfg |= DW_IC_CON_SPEED_FAST;
}
dev->clk = devm_clk_get(&pdev->dev, NULL);
if (!i2c_dw_plat_prepare_clk(dev, true)) {
......
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