[PATCH 1/3] can: c_can: Add d_can raminit support
AnilKumar Ch
anilkumar at ti.com
Wed Nov 14 13:08:23 EST 2012
Add D_CAN raminit support to C_CAN driver to enable D_CAN RAM,
which holds all the message objects during transmission or
receiving of data. This initialization/de-initialization should
be done in synchronous with D_CAN clock.
In case of AM335X-EVM (active user of D_CAN driver) message RAM is
controlled through control module register for both instances. So
control module register details is required to initialization or
de-initialization of message RAM according to instance number.
Control module memory resource is obtained from D_CAN dt node and
instance number obtained from device tree aliases node.
Signed-off-by: AnilKumar Ch <anilkumar at ti.com>
---
drivers/net/can/c_can/c_can.c | 12 +++++++++++
drivers/net/can/c_can/c_can.h | 3 +++
drivers/net/can/c_can/c_can_platform.c | 34 +++++++++++++++++++++++++++++++-
3 files changed, 48 insertions(+), 1 deletion(-)
diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
index e5180df..c15830c 100644
--- a/drivers/net/can/c_can/c_can.c
+++ b/drivers/net/can/c_can/c_can.c
@@ -233,6 +233,12 @@ static inline void c_can_pm_runtime_put_sync(const struct c_can_priv *priv)
pm_runtime_put_sync(priv->device);
}
+static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable)
+{
+ if (priv->ram_init)
+ priv->ram_init(priv, enable);
+}
+
static inline int get_tx_next_msg_obj(const struct c_can_priv *priv)
{
return (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) +
@@ -1090,6 +1096,7 @@ static int c_can_open(struct net_device *dev)
struct c_can_priv *priv = netdev_priv(dev);
c_can_pm_runtime_get_sync(priv);
+ c_can_reset_ram(priv, true);
/* open the can device */
err = open_candev(dev);
@@ -1118,6 +1125,7 @@ static int c_can_open(struct net_device *dev)
exit_irq_fail:
close_candev(dev);
exit_open_fail:
+ c_can_reset_ram(priv, false);
c_can_pm_runtime_put_sync(priv);
return err;
}
@@ -1131,6 +1139,8 @@ static int c_can_close(struct net_device *dev)
c_can_stop(dev);
free_irq(dev->irq, dev);
close_candev(dev);
+
+ c_can_reset_ram(priv, false);
c_can_pm_runtime_put_sync(priv);
return 0;
@@ -1188,6 +1198,7 @@ int c_can_power_down(struct net_device *dev)
c_can_stop(dev);
+ c_can_reset_ram(priv, false);
c_can_pm_runtime_put_sync(priv);
return 0;
@@ -1206,6 +1217,7 @@ int c_can_power_up(struct net_device *dev)
WARN_ON(priv->type != BOSCH_D_CAN);
c_can_pm_runtime_get_sync(priv);
+ c_can_reset_ram(priv, true);
/* Clear PDR and INIT bits */
val = priv->read_reg(priv, C_CAN_CTRL_EX_REG);
diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
index e5ed41d..419de5c 100644
--- a/drivers/net/can/c_can/c_can.h
+++ b/drivers/net/can/c_can/c_can.h
@@ -169,6 +169,9 @@ struct c_can_priv {
void *priv; /* for board-specific data */
u16 irqstatus;
enum c_can_dev_id type;
+ u32 __iomem *raminit_ctrlreg;
+ unsigned int instance;
+ void (*ram_init) (const struct c_can_priv *priv, bool enable);
};
struct net_device *alloc_c_can_dev(void);
diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index ee141613..2e61d69 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -38,6 +38,8 @@
#include "c_can.h"
+#define CAN_RAMINIT_START_MASK(i) (1 << (i))
+
/*
* 16-bit c_can registers can be arranged differently in the memory
* architecture of different implementations. For example: 16-bit
@@ -68,6 +70,24 @@ static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
writew(val, priv->base + 2 * priv->regs[index]);
}
+static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
+{
+ u32 val;
+
+ if (!priv->raminit_ctrlreg || (priv->instance < 0))
+ return;
+
+ val = readl(priv->raminit_ctrlreg);
+ if (enable) {
+ val &= ~CAN_RAMINIT_START_MASK(priv->instance);
+ val |= CAN_RAMINIT_START_MASK(priv->instance);
+ writel(val, priv->raminit_ctrlreg);
+ } else {
+ val &= ~CAN_RAMINIT_START_MASK(priv->instance);
+ writel(val, priv->raminit_ctrlreg);
+ }
+}
+
static struct platform_device_id c_can_id_table[] = {
[BOSCH_C_CAN_PLATFORM] = {
.name = KBUILD_MODNAME,
@@ -99,7 +119,7 @@ static int __devinit c_can_plat_probe(struct platform_device *pdev)
const struct of_device_id *match;
const struct platform_device_id *id;
struct pinctrl *pinctrl;
- struct resource *mem;
+ struct resource *mem, *res;
int irq;
struct clk *clk;
@@ -178,6 +198,18 @@ static int __devinit c_can_plat_probe(struct platform_device *pdev)
priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ priv->raminit_ctrlreg =
+ devm_request_and_ioremap(&pdev->dev, res);
+ if (!priv->raminit_ctrlreg)
+ dev_warn(&pdev->dev, "failed to obtain control memory\n");
+
+ if (pdev->dev.of_node)
+ pdev->id = of_alias_get_id(pdev->dev.of_node, "d_can");
+
+ priv->instance = pdev->id;
+ priv->ram_init = c_can_hw_raminit;
break;
default:
ret = -EINVAL;
--
1.7.9.5
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