[1/3] sp2: Add I2C driver for CIMaX SP2 common interface module

  Driver for the CIMaX SP2 common interface chip. It is very much based on
the existing cimax2 driver for cx23885, but should be more reusable. The
product has been sold with name Atmel T90FJR as well and the data sheets
for that chip seem to be publicly available.

It seems that the USB device that I have and the cx23885 based devices will
need to interact differently with the chip for the CAM operations. Thus
there is one callback function that is passed on to the sp2 driver
(see function sp2_ci_op_cam for that one).

IRQ functionality is not included currently (not needed by USB devices
and I don't have a PCIe device for development).

Signed-off-by: Olli Salonen <olli.salonen@iki.fi>
---
 drivers/media/dvb-frontends/Makefile   |   1 +
 drivers/media/dvb-frontends/sp2.c      | 411 +++++++++++++++++++++++++++++++++
 drivers/media/dvb-frontends/sp2.h      |  54 +++++
 drivers/media/dvb-frontends/sp2_priv.h |  49 ++++
 4 files changed, 515 insertions(+)
 create mode 100644 drivers/media/dvb-frontends/sp2.c
 create mode 100644 drivers/media/dvb-frontends/sp2.h
 create mode 100644 drivers/media/dvb-frontends/sp2_priv.h
  

On 08/06/2014 10:05 AM, Olli Salonen wrote:
> Driver for the CIMaX SP2 common interface chip. It is very much based on
> the existing cimax2 driver for cx23885, but should be more reusable. The
> product has been sold with name Atmel T90FJR as well and the data sheets
> for that chip seem to be publicly available.
>
> It seems that the USB device that I have and the cx23885 based devices will
> need to interact differently with the chip for the CAM operations. Thus
> there is one callback function that is passed on to the sp2 driver
> (see function sp2_ci_op_cam for that one).
>
> IRQ functionality is not included currently (not needed by USB devices
> and I don't have a PCIe device for development).
>
> Signed-off-by: Olli Salonen <olli.salonen@iki.fi>
> ---
>   drivers/media/dvb-frontends/Makefile   |   1 +
>   drivers/media/dvb-frontends/sp2.c      | 411 +++++++++++++++++++++++++++++++++
>   drivers/media/dvb-frontends/sp2.h      |  54 +++++
>   drivers/media/dvb-frontends/sp2_priv.h |  49 ++++
>   4 files changed, 515 insertions(+)
>   create mode 100644 drivers/media/dvb-frontends/sp2.c
>   create mode 100644 drivers/media/dvb-frontends/sp2.h
>   create mode 100644 drivers/media/dvb-frontends/sp2_priv.h
>
> diff --git a/drivers/media/dvb-frontends/Makefile b/drivers/media/dvb-frontends/Makefile
> index edf103d..3498b95 100644
> --- a/drivers/media/dvb-frontends/Makefile
> +++ b/drivers/media/dvb-frontends/Makefile
> @@ -107,6 +107,7 @@ obj-$(CONFIG_DVB_DRXK) += drxk.o
>   obj-$(CONFIG_DVB_TDA18271C2DD) += tda18271c2dd.o
>   obj-$(CONFIG_DVB_SI2165) += si2165.o
>   obj-$(CONFIG_DVB_A8293) += a8293.o
> +obj-$(CONFIG_DVB_SP2) += sp2.o
>   obj-$(CONFIG_DVB_TDA10071) += tda10071.o
>   obj-$(CONFIG_DVB_RTL2830) += rtl2830.o
>   obj-$(CONFIG_DVB_RTL2832) += rtl2832.o
> diff --git a/drivers/media/dvb-frontends/sp2.c b/drivers/media/dvb-frontends/sp2.c
> new file mode 100644
> index 0000000..c1b4d7e
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/sp2.c
> @@ -0,0 +1,411 @@
> +/*
> + * CIMaX SP2/SP2HF (Atmel T90FJR) CI driver
> + *
> + * Copyright (C) 2014 Olli Salonen <olli.salonen@iki.fi>
> + *
> + * Heavily based on CIMax2(R) SP2 driver in conjunction with NetUp Dual
> + * DVB-S2 CI card (cimax2) with following copyrights:
> + *
> + *  Copyright (C) 2009 NetUP Inc.
> + *  Copyright (C) 2009 Igor M. Liplianin <liplianin@netup.ru>
> + *  Copyright (C) 2009 Abylay Ospan <aospan@netup.ru>
> + *
> + *    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; either version 2 of the License, or
> + *    (at your option) any later version.
> + *
> + *    This program is distributed in the hope that it will be useful,
> + *    but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *    GNU General Public License for more details.
> + */
> +
> +#include "sp2_priv.h"
> +
> +static int sp2_read_i2c(struct sp2 *s, u8 reg, u8 *buf, int len)
> +{
> +	int ret;
> +	struct i2c_client *client = s->client;
> +	struct i2c_adapter *adap = client->adapter;
> +	struct i2c_msg msg[] = {
> +		{
> +			.addr = client->addr,
> +			.flags = 0,
> +			.buf = &reg,
> +			.len = 1
> +		}, {
> +			.addr = client->addr,
> +			.flags	= I2C_M_RD,
> +			.buf = buf,
> +			.len = len
> +		}
> +	};
> +
> +	ret = i2c_transfer(adap, msg, 2);
> +
> +	if (ret != 2) {
> +		dev_err(&client->dev, "i2c read error, reg = 0x%02x, status = %d\n",
> +				reg, ret);
> +		return -1;
> +	}

Could you define error code here? I know a lot of old drivers were using 
just -1, but for new driver we could try do better. Return possible 
error from i2c_transfer() and if it returns wrong amount of messages (0 
or 1 in that case) then change -EIO.

I looked from I2C documentation and I think -EIO fits best

Documentation/i2c/fault-codes

EIO
	This rather vague error means something went wrong when
	performing an I/O operation.  Use a more specific fault
	code when you can.


> +
> +	dev_dbg(&s->client->dev, "addr=0x%04x, reg = 0x%02x, data = %02x\n",
> +				client->addr, reg, buf[0]);
> +
> +	return 0;
> +}
> +
> +static int sp2_write_i2c(struct sp2 *s, u8 reg, u8 *buf, int len)
> +{
> +	int ret;
> +	u8 buffer[35];
> +	struct i2c_client *client = s->client;
> +	struct i2c_adapter *adap = client->adapter;
> +	struct i2c_msg msg = {
> +		.addr = client->addr,
> +		.flags = 0,
> +		.buf = &buffer[0],
> +		.len = len + 1
> +	};
> +
> +	if ((len + 1) > sizeof(buffer)) {
> +		dev_err(&client->dev, "i2c wr reg=%02x: len=%d is too big!\n",
> +				reg, len);
> +		return -EINVAL;
> +	}
> +
> +	buffer[0] = reg;
> +	memcpy(&buffer[1], buf, len);
> +
> +	ret = i2c_transfer(adap, &msg, 1);
> +
> +	if (ret != 1) {
> +		dev_err(&client->dev, "i2c write error, reg = 0x%02x, status = %d\n",
> +				reg, ret);
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int sp2_ci_op_cam(struct dvb_ca_en50221 *en50221, int slot, u8 acs,
> +			u8 read, int addr, u8 data)
> +{
> +	struct sp2 *s = en50221->data;
> +	u8 store;
> +	int mem, ret;
> +	int (*ci_op_cam)(void*, u8, int, u8, int*) = s->ci_control;
> +
> +	dev_dbg(&s->client->dev, "slot=%d, acs=0x%02x, addr=0x%04x, data = 0x%02x",
> +			slot, acs, addr, data);
> +
> +	if (slot != 0)
> +		return -EINVAL;
> +
> +	/* change module access type between IO space and attribute memory
> +	   when needed */

See Documentation/CodingStyle Chapter 8: Commenting.

/*
  * change module access type between IO space and attribute memory
  * when needed
  */

checkpatch.pl ?

> +	if (s->module_access_type != acs) {
> +		ret = sp2_read_i2c(s, 0x00, &store, 1);
> +
> +		if (ret)
> +			return ret;
> +
> +		store &= ~(SP2_MOD_CTL_ACS1 | SP2_MOD_CTL_ACS0);
> +		store |= acs;
> +
> +		ret = sp2_write_i2c(s, 0x00, &store, 1);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	s->module_access_type = acs;
> +
> +	/* implementation of ci_op_cam is device specific */
> +	if (ci_op_cam) {
> +		ret = ci_op_cam(s->priv, read, addr, data, &mem);
> +	} else {
> +		dev_err(&s->client->dev, "callback not defined");
> +		return -EINVAL;
> +	}
> +
> +	if (ret)
> +		return -EREMOTEIO;

Maybe it could be good idea to return original error code from the 
bridge driver here too. EREMOTEIO is USB specific error.

> +
> +	if (read) {
> +		dev_dbg(&s->client->dev, "cam read, addr=0x%04x, data = 0x%04x",
> +				addr, mem);
> +		return mem;
> +	} else {
> +		return 0;
> +	}
> +}
> +
> +int sp2_ci_read_attribute_mem(struct dvb_ca_en50221 *en50221,
> +				int slot, int addr)
> +{
> +	return sp2_ci_op_cam(en50221, slot, SP2_CI_ATTR_ACS,
> +			SP2_CI_RD, addr, 0);
> +}
> +
> +int sp2_ci_write_attribute_mem(struct dvb_ca_en50221 *en50221,
> +				int slot, int addr, u8 data)
> +{
> +	return sp2_ci_op_cam(en50221, slot, SP2_CI_ATTR_ACS,
> +			SP2_CI_WR, addr, data);
> +}
> +
> +int sp2_ci_read_cam_control(struct dvb_ca_en50221 *en50221,
> +				int slot, u8 addr)
> +{
> +	return sp2_ci_op_cam(en50221, slot, SP2_CI_IO_ACS,
> +			SP2_CI_RD, addr, 0);
> +}
> +
> +int sp2_ci_write_cam_control(struct dvb_ca_en50221 *en50221,
> +				int slot, u8 addr, u8 data)
> +{
> +	return sp2_ci_op_cam(en50221, slot, SP2_CI_IO_ACS,
> +			SP2_CI_WR, addr, data);
> +}
> +
> +int sp2_ci_slot_reset(struct dvb_ca_en50221 *en50221, int slot)
> +{
> +	struct sp2 *s = en50221->data;
> +	u8 buf;
> +	int ret;
> +
> +	if (slot != 0)
> +		return -EINVAL;
> +
> +	usleep_range(500, 600);

That sleep has no idea. It is there likely workaround some other bug. 
You should not need never wait before I/O like that - but likely after 
in order to wait hw ready. Underlying adapter is I2C here and adapter 
should be ready without a waiting.

> +
> +	/* RST on */
> +	buf = SP2_MOD_CTL_RST;
> +	ret = sp2_write_i2c(s, 0x00, &buf, 1);
> +
> +	if (ret)
> +		return ret;
> +
> +	usleep_range(500, 600);
> +
> +	/* RST off */
> +	buf = 0x00;
> +	ret = sp2_write_i2c(s, 0x00, &buf, 1);
> +
> +	msleep(1000);
> +
> +	return 0;

return value from previous I2C op is discarded mistakenly?

> +}
> +
> +int sp2_ci_slot_shutdown(struct dvb_ca_en50221 *en50221, int slot)
> +{
> +	/* not implemented */
> +	return 0;
> +}
> +
> +int sp2_ci_slot_ts_enable(struct dvb_ca_en50221 *en50221, int slot)
> +{
> +	struct sp2 *s = en50221->data;
> +	u8 buf;
> +
> +	if (slot != 0)
> +		return -EINVAL;
> +
> +	sp2_read_i2c(s, 0x00, &buf, 1);
> +
> +	/* disable bypass and enable TS */
> +	buf |= (SP2_MOD_CTL_TSOEN | SP2_MOD_CTL_TSIEN);
> +	return sp2_write_i2c(s, 0, &buf, 1);
> +}
> +
> +int sp2_ci_poll_slot_status(struct dvb_ca_en50221 *en50221,
> +				int slot, int open)
> +{
> +	struct sp2 *s = en50221->data;
> +	u8 buf[2];
> +	int ret;
> +
> +	/* CAM module INSERT/REMOVE processing. slow operation because of i2c
> +	 * transfers */

multiline comment style

> +	if (time_after(jiffies, s->next_status_checked_time)) {
> +		ret = sp2_read_i2c(s, 0x00, buf, 1);
> +		s->next_status_checked_time = jiffies +	msecs_to_jiffies(1000);
> +
> +		if (ret)
> +			return 0;
> +
> +		if (buf[0] & SP2_MOD_CTL_DET)
> +			s->status = DVB_CA_EN50221_POLL_CAM_PRESENT |
> +					DVB_CA_EN50221_POLL_CAM_READY;
> +		else
> +			s->status = 0;
> +	}

Adds one sec throttle for CAM polling, which is imho good. I have never 
understood why it is polled so rapidly...

> +
> +	return s->status;
> +}
> +
> +int sp2_init(struct sp2 *s)
> +{
> +	int ret = 0;
> +	u8 buf;
> +	u8 cimax_init[34] = {
> +		0x00, /* module A control*/
> +		0x00, /* auto select mask high A */
> +		0x00, /* auto select mask low A */
> +		0x00, /* auto select pattern high A */
> +		0x00, /* auto select pattern low A */
> +		0x44, /* memory access time A, 600 ns */
> +		0x00, /* invert input A */
> +		0x00, /* RFU */
> +		0x00, /* RFU */
> +		0x00, /* module B control*/
> +		0x00, /* auto select mask high B */
> +		0x00, /* auto select mask low B */
> +		0x00, /* auto select pattern high B */
> +		0x00, /* auto select pattern low B */
> +		0x44, /* memory access time B, 600 ns */
> +		0x00, /* invert input B */
> +		0x00, /* RFU */
> +		0x00, /* RFU */
> +		0x00, /* auto select mask high Ext */
> +		0x00, /* auto select mask low Ext */
> +		0x00, /* auto select pattern high Ext */
> +		0x00, /* auto select pattern low Ext */
> +		0x00, /* RFU */
> +		0x02, /* destination - module A */
> +		0x01, /* power control reg, VCC power on */
> +		0x00, /* RFU */
> +		0x00, /* int status read only */
> +		0x00, /* Interrupt Mask Register */
> +		0x05, /* EXTINT=active-high, INT=push-pull */
> +		0x00, /* USCG1 */
> +		0x04, /* ack active low */
> +		0x00, /* LOCK = 0 */
> +		0x22, /* unknown */
> +		0x00, /* synchronization? */
> +	};
> +
> +	s->ca.owner = THIS_MODULE;
> +	s->ca.read_attribute_mem = sp2_ci_read_attribute_mem;
> +	s->ca.write_attribute_mem = sp2_ci_write_attribute_mem;
> +	s->ca.read_cam_control = sp2_ci_read_cam_control;
> +	s->ca.write_cam_control = sp2_ci_write_cam_control;
> +	s->ca.slot_reset = sp2_ci_slot_reset;
> +	s->ca.slot_shutdown = sp2_ci_slot_shutdown;
> +	s->ca.slot_ts_enable = sp2_ci_slot_ts_enable;
> +	s->ca.poll_slot_status = sp2_ci_poll_slot_status;
> +	s->ca.data = s;
> +	s->module_access_type = 0;
> +
> +	/* initialize all regs */
> +	ret = sp2_write_i2c(s, 0x00, &cimax_init[0], 34);
> +	if (ret)
> +		goto err;
> +
> +	/* lock registers */
> +	buf = 1;
> +	ret = sp2_write_i2c(s, 0x1f, &buf, 1);
> +	if (ret)
> +		goto err;
> +
> +	/* power on slots */
> +	ret = sp2_write_i2c(s, 0x18, &buf, 1);
> +	if (ret)
> +		goto err;
> +
> +	ret = dvb_ca_en50221_init(s->dvb_adap, &s->ca, 0, 1);
> +	if (ret)
> +		goto err;
> +
> +	return 0;
> +
> +err:
> +	dev_dbg(&s->client->dev, "init failed=%d\n", ret);
> +	return ret;
> +}
> +
> +int sp2_exit(struct i2c_client *client)
> +{
> +	struct sp2 *s;
> +
> +	if (client == NULL)
> +		return 0;
> +
> +	s = i2c_get_clientdata(client);
> +	if (s == NULL)
> +		return 0;
> +
> +	if (s->ca.data == NULL)
> +		return 0;
> +
> +	dvb_ca_en50221_release(&s->ca);
> +
> +	return 0;
> +}
> +
> +static int sp2_probe(struct i2c_client *client,
> +		const struct i2c_device_id *id)
> +{
> +	struct sp2_config *cfg = client->dev.platform_data;
> +	struct sp2 *s;
> +	int ret;
> +
> +	s = kzalloc(sizeof(struct sp2), GFP_KERNEL);
> +	if (!s) {
> +		ret = -ENOMEM;
> +		dev_err(&client->dev, "kzalloc() failed\n");
> +		goto err;
> +	}
> +
> +	s->client = client;
> +	s->dvb_adap = cfg->dvb_adap;
> +	s->priv = cfg->priv;
> +	s->ci_control = cfg->ci_control;
> +
> +	i2c_set_clientdata(client, s);
> +
> +	ret = sp2_init(s);
> +	if (ret)
> +		goto err;
> +
> +	dev_info(&s->client->dev, "CIMaX SP2 successfully attached\n");
> +	return 0;
> +err:
> +	dev_dbg(&client->dev, "init failed=%d\n", ret);
> +	kfree(s);
> +
> +	return ret;
> +}
> +
> +static int sp2_remove(struct i2c_client *client)
> +{
> +	struct si2157 *s = i2c_get_clientdata(client);
> +
> +	sp2_exit(client);
> +	kfree(s);
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id sp2_id[] = {
> +	{"sp2", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, sp2_id);
> +
> +static struct i2c_driver sp2_driver = {
> +	.driver = {
> +		.owner	= THIS_MODULE,
> +		.name	= "sp2",
> +	},
> +	.probe		= sp2_probe,
> +	.remove		= sp2_remove,
> +	.id_table	= sp2_id,
> +};
> +
> +module_i2c_driver(sp2_driver);
> +
> +MODULE_DESCRIPTION("CIMaX SP2/HF CI driver");
> +MODULE_AUTHOR("Olli Salonen <olli.salonen@iki.fi>");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/media/dvb-frontends/sp2.h b/drivers/media/dvb-frontends/sp2.h
> new file mode 100644
> index 0000000..31ba6ba
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/sp2.h
> @@ -0,0 +1,54 @@
> +/*
> + * CIMaX SP2/HF CI driver
> + *
> + * Copyright (C) 2014 Olli Salonen <olli.salonen@iki.fi>
> + *
> + *    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; either version 2 of the License, or
> + *    (at your option) any later version.
> + *
> + *    This program is distributed in the hope that it will be useful,
> + *    but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *    GNU General Public License for more details.
> + */
> +
> +#ifndef SP2_H
> +#define SP2_H
> +
> +#include <linux/kconfig.h>
> +#include "dvb_frontend.h"

Maybe that include is not needed? There is no direct frontend relation?

> +#include "dvb_ca_en50221.h"
> +
> +/*
> + * I2C address
> + * 0x40 (port 0)
> + * 0x41 (port 1)
> + */
> +struct sp2_config {
> +	/* dvb_adapter to attach the ci to */
> +	struct dvb_adapter *dvb_adap;
> +
> +	/* function ci_control handles the device specific ci ops */
> +	void *ci_control;
> +
> +	/* priv is passed back to function ci_control */
> +	void *priv;
> +};
> +
> +extern int sp2_ci_read_attribute_mem(struct dvb_ca_en50221 *en50221,
> +					int slot, int addr);
> +extern int sp2_ci_write_attribute_mem(struct dvb_ca_en50221 *en50221,
> +					int slot, int addr, u8 data);
> +extern int sp2_ci_read_cam_control(struct dvb_ca_en50221 *en50221,
> +					int slot, u8 addr);
> +extern int sp2_ci_write_cam_control(struct dvb_ca_en50221 *en50221,
> +					int slot, u8 addr, u8 data);
> +extern int sp2_ci_slot_reset(struct dvb_ca_en50221 *en50221, int slot);
> +extern int sp2_ci_slot_shutdown(struct dvb_ca_en50221 *en50221, int slot);
> +extern int sp2_ci_slot_ts_enable(struct dvb_ca_en50221 *en50221, int slot);
> +extern int sp2_ci_poll_slot_status(struct dvb_ca_en50221 *en50221,
> +					int slot, int open);
> +
> +#endif
> diff --git a/drivers/media/dvb-frontends/sp2_priv.h b/drivers/media/dvb-frontends/sp2_priv.h
> new file mode 100644
> index 0000000..7099fb9
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/sp2_priv.h
> @@ -0,0 +1,49 @@
> +/*
> + * CIMaX SP2/HF CI driver
> + *
> + * Copyright (C) 2014 Olli Salonen <olli.salonen@iki.fi>
> + *
> + *    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; either version 2 of the License, or
> + *    (at your option) any later version.
> + *
> + *    This program is distributed in the hope that it will be useful,
> + *    but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *    GNU General Public License for more details.
> + */
> +
> +#ifndef SP2_PRIV_H
> +#define SP2_PRIV_H
> +
> +#include "sp2.h"
> +
> +/* state struct */
> +struct sp2 {
> +	int status;
> +	struct i2c_client *client;
> +	struct dvb_adapter *dvb_adap;
> +	struct dvb_ca_en50221 ca;
> +	int module_access_type;
> +	unsigned long next_status_checked_time;
> +	void *priv;
> +	void *ci_control;
> +};
> +
> +#define SP2_CI_ATTR_ACS		0x00
> +#define SP2_CI_IO_ACS		0x04
> +#define SP2_CI_WR		0
> +#define SP2_CI_RD		1
> +
> +/* Module control register (0x00 module A, 0x09 module B) bits */
> +#define SP2_MOD_CTL_DET		0x01
> +#define SP2_MOD_CTL_AUTO	0x02
> +#define SP2_MOD_CTL_ACS0	0x04
> +#define SP2_MOD_CTL_ACS1	0x08
> +#define SP2_MOD_CTL_HAD		0x10
> +#define SP2_MOD_CTL_TSIEN	0x20
> +#define SP2_MOD_CTL_TSOEN	0x40
> +#define SP2_MOD_CTL_RST		0x80
> +
> +#endif
>


Reviewed-by: Antti Palosaari <crope@iki.fi>

None of those findings are critical. However I hope you double check and 
fix if there is any relevant enough.

regards
Antti
  

Thank you Antti for the review. I'll submit another version of the
patch in the coming days.

Cheers,
-olli

On 7 August 2014 19:28, Antti Palosaari <crope@iki.fi> wrote:
> Reviewed-by: Antti Palosaari <crope@iki.fi>
>
> None of those findings are critical. However I hope you double check and fix
> if there is any relevant enough.
>
> regards
> Antti
>
> --
> http://palosaari.fi/
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