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can: flexcan: Use a regulator to control the CAN transceiver

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Instead of using a GPIO to turn on/off the CAN transceiver, it is better to
use a regulator as some systems may use a PMIC to power the CAN transceiver.

Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Fabio Estevam 2013-06-10 23:12:57 -03:00 committed by Marc Kleine-Budde
parent 30caa4b763
commit b7c4114b07
4 changed files with 28 additions and 61 deletions
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2
Documentation/devicetree/bindings/net/can/fsl-flexcan.txt
View File

@ -16,6 +16,8 @@ Optional properties:
- clock-frequency : The oscillator frequency driving the flexcan device
- xceiver-supply: Regulator that powers the CAN transceiver
Example:
can@1c000 {

12
arch/arm/boot/dts/imx28-evk.dts
View File

@ -155,12 +155,14 @@
can0: can@80032000 {
pinctrl-names = "default";
pinctrl-0 = <&can0_pins_a>;
xceiver-supply = <&reg_can_3v3>;
status = "okay";
};
can1: can@80034000 {
pinctrl-names = "default";
pinctrl-0 = <&can1_pins_a>;
xceiver-supply = <&reg_can_3v3>;
status = "okay";
};
};
@ -319,6 +321,16 @@
gpio = <&gpio3 30 0>;
enable-active-high;
};
reg_can_3v3: can-3v3 {
compatible = "regulator-fixed";
regulator-name = "can-3v3";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
gpio = <&gpio2 13 0>;
enable-active-high;
};
};
sound {

50
arch/arm/mach-mxs/mach-mxs.c
View File

@ -14,7 +14,6 @@
#include <linux/clk/mxs.h>
#include <linux/clkdev.h>
#include <linux/clocksource.h>
#include <linux/can/platform/flexcan.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio.h>
@ -60,41 +59,6 @@ static inline void __mxs_togl(u32 mask, void __iomem *reg)
__raw_writel(mask, reg + MXS_TOG_ADDR);
}
/*
* MX28EVK_FLEXCAN_SWITCH is shared between both flexcan controllers
*/
#define MX28EVK_FLEXCAN_SWITCH MXS_GPIO_NR(2, 13)
static int flexcan0_en, flexcan1_en;
static void mx28evk_flexcan_switch(void)
{
if (flexcan0_en || flexcan1_en)
gpio_set_value(MX28EVK_FLEXCAN_SWITCH, 1);
else
gpio_set_value(MX28EVK_FLEXCAN_SWITCH, 0);
}
static void mx28evk_flexcan0_switch(int enable)
{
flexcan0_en = enable;
mx28evk_flexcan_switch();
}
static void mx28evk_flexcan1_switch(int enable)
{
flexcan1_en = enable;
mx28evk_flexcan_switch();
}
static struct flexcan_platform_data flexcan_pdata[2];
static struct of_dev_auxdata mxs_auxdata_lookup[] __initdata = {
OF_DEV_AUXDATA("fsl,imx28-flexcan", 0x80032000, NULL, &flexcan_pdata[0]),
OF_DEV_AUXDATA("fsl,imx28-flexcan", 0x80034000, NULL, &flexcan_pdata[1]),
{ /* sentinel */ }
};
#define OCOTP_WORD_OFFSET 0x20
#define OCOTP_WORD_COUNT 0x20
@ -254,15 +218,6 @@ static void __init imx28_evk_init(void)
mxs_saif_clkmux_select(MXS_DIGCTL_SAIF_CLKMUX_EXTMSTR0);
}
static void __init imx28_evk_post_init(void)
{
if (!gpio_request_one(MX28EVK_FLEXCAN_SWITCH, GPIOF_DIR_OUT,
"flexcan-switch")) {
flexcan_pdata[0].transceiver_switch = mx28evk_flexcan0_switch;
flexcan_pdata[1].transceiver_switch = mx28evk_flexcan1_switch;
}
}
static int apx4devkit_phy_fixup(struct phy_device *phy)
{
phy->dev_flags |= MICREL_PHY_50MHZ_CLK;
@ -374,13 +329,10 @@ static void __init mxs_machine_init(void)
cfa10049_init();
of_platform_populate(NULL, of_default_bus_match_table,
mxs_auxdata_lookup, NULL);
NULL, NULL);
if (of_machine_is_compatible("karo,tx28"))
tx28_post_init();
if (of_machine_is_compatible("fsl,imx28-evk"))
imx28_evk_post_init();
}
#define MX23_CLKCTRL_RESET_OFFSET 0x120

25
drivers/net/can/flexcan.c
View File

@ -24,7 +24,6 @@
#include <linux/can/dev.h>
#include <linux/can/error.h>
#include <linux/can/led.h>
#include <linux/can/platform/flexcan.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/if_arp.h>
@ -37,6 +36,7 @@
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#define DRV_NAME "flexcan"
@ -211,6 +211,7 @@ struct flexcan_priv {
struct clk *clk_per;
struct flexcan_platform_data *pdata;
const struct flexcan_devtype_data *devtype_data;
struct regulator *reg_xceiver;
};
static struct flexcan_devtype_data fsl_p1010_devtype_data = {
@ -258,15 +259,6 @@ static inline void flexcan_write(u32 val, void __iomem *addr)
}
#endif
/*
* Swtich transceiver on or off
*/
static void flexcan_transceiver_switch(const struct flexcan_priv *priv, int on)
{
if (priv->pdata && priv->pdata->transceiver_switch)
priv->pdata->transceiver_switch(on);
}
static inline int flexcan_has_and_handle_berr(const struct flexcan_priv *priv,
u32 reg_esr)
{
@ -799,7 +791,11 @@ static int flexcan_chip_start(struct net_device *dev)
if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES)
flexcan_write(0x0, &regs->rxfgmask);
flexcan_transceiver_switch(priv, 1);
if (priv->reg_xceiver) {
err = regulator_enable(priv->reg_xceiver);
if (err)
goto out;
}
/* synchronize with the can bus */
reg_mcr = flexcan_read(&regs->mcr);
@ -842,7 +838,8 @@ static void flexcan_chip_stop(struct net_device *dev)
reg |= FLEXCAN_MCR_MDIS | FLEXCAN_MCR_HALT;
flexcan_write(reg, &regs->mcr);
flexcan_transceiver_switch(priv, 0);
if (priv->reg_xceiver)
regulator_disable(priv->reg_xceiver);
priv->can.state = CAN_STATE_STOPPED;
return;
@ -1084,6 +1081,10 @@ static int flexcan_probe(struct platform_device *pdev)
priv->pdata = pdev->dev.platform_data;
priv->devtype_data = devtype_data;
priv->reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
if (IS_ERR(priv->reg_xceiver))
priv->reg_xceiver = NULL;
netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);
dev_set_drvdata(&pdev->dev, dev);