[PATCH 2/4] can: c_can: Add d_can raminit support
Vaibhav Hiremath
hvaibhav at ti.com
Tue Sep 4 03:36:45 EDT 2012
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 at ti.com>
>>> ---
>>> 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,
Vaibhav
>>
>> Marc
>>
>>> + goto exit_free_device;
>>> + }
>>> + priv->ram_init = pdata->ram_init;
>>> + priv->instance = pdata->instance;
>>> break;
>>> default:
>>> ret = -EINVAL;
>>> diff --git a/include/linux/can/platform/c_can.h b/include/linux/can/platform/c_can.h
>>> new file mode 100644
>>> index 0000000..84b27d2
>>> --- /dev/null
>>> +++ b/include/linux/can/platform/c_can.h
>>> @@ -0,0 +1,36 @@
>>> +/*
>>> + * C_CAN controller driver platform header
>>> + *
>>> + * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
>>> + *
>>> + * Bosch C_CAN/D_CAN controller is compliant to CAN protocol version 2.0
>>> + * part A and B.
>>> + *
>>> + * This program is free software; you can redistribute it and/or
>>> + * modify it under the terms of the GNU General Public License as
>>> + * published by the Free Software Foundation version 2.
>>> + *
>>> + * This program is distributed "as is" WITHOUT ANY WARRANTY of any
>>> + * kind, whether express or implied; without even the implied warranty
>>> + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>>> + * GNU General Public License for more details.
>>> + */
>>> +
>>> +#ifndef __CAN_PLATFORM_C_CAN_H__
>>> +#define __CAN_PLATFORM_C_CAN_H__
>>> +
>>> +/**
>>> + * struct c_can_platform_data - C_CAN/D_CAN Platform Data
>>> + *
>>> + * @instance: CAN instance, required for d_can raminit
>>> + * @ram_init: CAN RAM initialization
>>> + *
>>> + * Platform data structure to get all platform specific settings.
>>> + * this structure also accounts the fact that the IP may have different
>>> + * RAM for different SOC's
>>> + */
>>> +struct c_can_platform_data {
>>> + unsigned int instance;
>>> + void (*ram_init) (unsigned int instance, bool enable);
>>> +};
>>> +#endif
>>>
>>
>>
>> --
>> 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 |
>>
>>
>
>
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