On 09/04/2012 09:36 AM, Vaibhav Hiremath wrote:
>
>
> On 9/4/2012 11:44 AM, AnilKumar, Chimata wrote:
>> Hi Marc,
>>
>> On Tue, Sep 04, 2012 at 02:09:15, Marc Kleine-Budde wrote:
>>> On 09/03/2012 01:52 PM, AnilKumar Ch wrote:
>>>> Add D_CAN raminit support to C_CAN driver to enable D_CAN RAM.
>>>> DCAN RAM holds all the message objects during transmission or
>>>> receiving of data. This initialization/de-initialization should
>>>> be done in synchronous with D_CAN clock.
>>>>
>>>> Signed-off-by: AnilKumar Ch <anilkumar@xxxxxx>
>>>> ---
>>>> drivers/net/can/c_can/c_can.c | 13 ++++++++++++
>>>> drivers/net/can/c_can/c_can.h | 2 ++
>>>> drivers/net/can/c_can/c_can_platform.c | 10 +++++++++
>>>> include/linux/can/platform/c_can.h | 36 ++++++++++++++++++++++++++++++++
>>>> 4 files changed, 61 insertions(+)
>>>> create mode 100644 include/linux/can/platform/c_can.h
>>>>
>>>> diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
>>>> index aa6c5eb..c175410 100644
>>>> --- a/drivers/net/can/c_can/c_can.c
>>>> +++ b/drivers/net/can/c_can/c_can.c
>>>> @@ -214,6 +214,12 @@ 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->instance, 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) +
>>>> @@ -1071,6 +1077,8 @@ static int c_can_open(struct net_device *dev)
>>>> struct c_can_priv *priv = netdev_priv(dev);
>>>>
>>>> c_can_pm_runtime_get_sync(priv);
>>>> + /* Initialize DCAN RAM */
>>>> + c_can_reset_ram(priv, true);
>>>>
>>>> /* open the can device */
>>>> err = open_candev(dev);
>>>> @@ -1099,6 +1107,8 @@ static int c_can_open(struct net_device *dev)
>>>> exit_irq_fail:
>>>> close_candev(dev);
>>>> exit_open_fail:
>>>> + /* De-Initialize DCAN RAM */
>>>> + c_can_reset_ram(priv, false);
>>>> c_can_pm_runtime_put_sync(priv);
>>>> return err;
>>>> }
>>>> @@ -1112,6 +1122,9 @@ static int c_can_close(struct net_device *dev)
>>>> c_can_stop(dev);
>>>> free_irq(dev->irq, dev);
>>>> close_candev(dev);
>>>> +
>>>> + /* De-Initialize DCAN RAM */
>>>> + c_can_reset_ram(priv, false);
>>>> c_can_pm_runtime_put_sync(priv);
>>>>
>>>> return 0;
>>>> diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
>>>> index 1437a6d..5f6339c 100644
>>>> --- a/drivers/net/can/c_can/c_can.h
>>>> +++ b/drivers/net/can/c_can/c_can.h
>>>> @@ -166,6 +166,8 @@ struct c_can_priv {
>>>> unsigned int tx_echo;
>>>> void *priv; /* for board-specific data */
>>>> u16 irqstatus;
>>>> + unsigned int instance;
>>>> + void (*ram_init) (unsigned int instance, 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 c351975..c6963b2 100644
>>>> --- a/drivers/net/can/c_can/c_can_platform.c
>>>> +++ b/drivers/net/can/c_can/c_can_platform.c
>>>> @@ -34,6 +34,7 @@
>>>> #include <linux/of_device.h>
>>>> #include <linux/pm_runtime.h>
>>>> #include <linux/pinctrl/consumer.h>
>>>> +#include <linux/can/platform/c_can.h>
>>>>
>>>> #include <linux/can/dev.h>
>>>>
>>>> @@ -98,6 +99,7 @@ static int __devinit c_can_plat_probe(struct platform_device *pdev)
>>>> struct net_device *dev;
>>>> struct c_can_priv *priv;
>>>> const struct of_device_id *match;
>>>> + struct c_can_platform_data *pdata = NULL;
>>>> const struct platform_device_id *id;
>>>> struct pinctrl *pinctrl;
>>>> struct resource *mem;
>>>> @@ -179,6 +181,14 @@ 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;
>>>> + pdata = pdev->dev.platform_data;
>>>> + if (!pdata) {
>>>> + dev_err(&pdev->dev, "d_can platform data missing\n");
>>>> + ret = -EINVAL;
>>>
>>> Is the ram_init mandatory on all d_can? There might be non omap d_can users.
>>
>> As per AM335x specifications d_can module should have ram_init.
>> In that case it's better to print warning and break the switch.
>>
>
> As far as I know, "ram_init" is part of IP spec, how it is controlled
> does varies based on SoC integration.
Thanks for your insight. Leave the code as it is. If there is another
d_can user we know more and will improve/fix the code :)
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
Attachment:
signature.asc
Description: OpenPGP digital signature
