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spi: rockchip: set higher io driver when sclk higher than 24MHz

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Change-Id: I963c92eab7f7bff0b32e2ac262aa79f0667f39ee
Signed-off-by: Huibin Hong <huibin.hong@rock-chips.com>
Signed-off-by: Yifeng Zhao <zyf@rock-chips.com>
This commit is contained in:
Huibin Hong
2018-02-24 20:57:22 +08:00
committed by Tao Huang
parent e13191bf15
commit 87dbea63d5
1 changed files with 24 additions and 0 deletions
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drivers/spi/spi-rockchip.c
+24
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@@ -19,6 +19,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/devinfo.h>
#include <linux/platform_device.h>
#include <linux/spi/spi.h>
#include <linux/pm_runtime.h>
@@ -148,6 +149,8 @@
/* sclk_out: spi master internal logic in rk3x can support 50Mhz */
#define MAX_SCLK_OUT 50000000
/* max sclk of driver strength 4mA */
#define IO_DRIVER_4MA_MAX_SCLK_OUT 24000000
/*
* SPI_CTRLR1 is 16-bits, so we should support lengths of 0xffff + 1. However,
@@ -209,6 +212,7 @@ struct rockchip_spi {
struct rockchip_spi_dma_data dma_rx;
struct rockchip_spi_dma_data dma_tx;
struct dma_slave_caps dma_caps;
struct pinctrl_state *high_speed_state;
};
static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
@@ -553,6 +557,19 @@ static void rockchip_spi_config(struct rockchip_spi *rs)
div = DIV_ROUND_UP(rs->max_freq, rs->speed);
div = (div + 1) & 0xfffe;
/*
* If speed is larger than IO_DRIVER_4MA_MAX_SCLK_OUT,
* set higher driver strength.
*/
if (rs->high_speed_state) {
if (rs->speed > IO_DRIVER_4MA_MAX_SCLK_OUT)
pinctrl_select_state(rs->dev->pins->p,
rs->high_speed_state);
else
pinctrl_select_state(rs->dev->pins->p,
rs->dev->pins->default_state);
}
/* Rx sample delay is expressed in parent clock cycles (max 3) */
rsd = DIV_ROUND_CLOSEST(rs->rsd_nsecs * (rs->max_freq >> 8),
1000000000 >> 8);
@@ -792,6 +809,13 @@ static int rockchip_spi_probe(struct platform_device *pdev)
master->dma_rx = rs->dma_rx.ch;
}
rs->high_speed_state = pinctrl_lookup_state(rs->dev->pins->p,
"high_speed");
if (IS_ERR_OR_NULL(rs->high_speed_state)) {
dev_warn(&pdev->dev, "no high_speed pinctrl state\n");
rs->high_speed_state = NULL;
}
ret = devm_spi_register_master(&pdev->dev, master);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to register master\n");