Re: [PATCH v2 02/15] [media] cxd2880-spi: Add support for CXD2008 SPI interface

From: Mauro Carvalho Chehab
Date: Tue Jun 13 2017 - 07:55:30 EST


Em Fri, 14 Apr 2017 11:08:23 +0900
<Yasunari.Takiguchi@xxxxxxxx> escreveu:

> From: Yasunari Takiguchi <Yasunari.Takiguchi@xxxxxxxx>
>
> This is the SPI adapter part of the driver for the
> Sony CXD2880 DVB-T2/T tuner + demodulator.
>
> Signed-off-by: Yasunari Takiguchi <Yasunari.Takiguchi@xxxxxxxx>
> Signed-off-by: Masayuki Yamamoto <Masayuki.Yamamoto@xxxxxxxx>
> Signed-off-by: Hideki Nozawa <Hideki.Nozawa@xxxxxxxx>
> Signed-off-by: Kota Yonezawa <Kota.Yonezawa@xxxxxxxx>
> Signed-off-by: Toshihiko Matsumoto <Toshihiko.Matsumoto@xxxxxxxx>
> Signed-off-by: Satoshi Watanabe <Satoshi.C.Watanabe@xxxxxxxx>
> ---
> drivers/media/spi/cxd2880-spi.c | 728 ++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 728 insertions(+)
> create mode 100644 drivers/media/spi/cxd2880-spi.c
>
> diff --git a/drivers/media/spi/cxd2880-spi.c b/drivers/media/spi/cxd2880-spi.c
> new file mode 100644
> index 000000000000..82e122349055
> --- /dev/null
> +++ b/drivers/media/spi/cxd2880-spi.c
> @@ -0,0 +1,728 @@
> +/*
> + * cxd2880-spi.c
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * SPI adapter
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * 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 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/spi/spi.h>
> +
> +#include "dvb_demux.h"
> +#include "dmxdev.h"
> +#include "dvb_frontend.h"
> +#include "cxd2880.h"
> +
> +#define CXD2880_MAX_FILTER_SIZE 32
> +#define BURST_WRITE_MAX 128
> +#define MAX_TRANS_PACKET 300
> +
> +struct cxd2880_ts_buf_info {
> + u8 read_ready;
> + u8 almost_full;
> + u8 almost_empty;
> + u8 overflow;
> + u8 underflow;
> + u16 packet_num;
> +};
> +
> +struct cxd2880_pid_config {
> + u8 is_enable;
> + u16 pid;
> +};
> +
> +struct cxd2880_pid_filter_config {
> + u8 is_negative;
> + struct cxd2880_pid_config pid_config[CXD2880_MAX_FILTER_SIZE];
> +};
> +
> +struct cxd2880_dvb_spi {
> + struct dvb_frontend dvb_fe;
> + struct dvb_adapter adapter;
> + struct dvb_demux demux;
> + struct dmxdev dmxdev;
> + struct dmx_frontend dmx_fe;
> + struct task_struct *cxd2880_ts_read_thread;
> + struct spi_device *spi;
> + struct mutex spi_mutex; /* For SPI access exclusive control */
> + int feed_count;
> + int all_pid_feed_count;
> + u8 *ts_buf;
> + struct cxd2880_pid_filter_config filter_config;
> +};
> +
> +DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
> +
> +static int cxd2880_write_spi(struct spi_device *spi, u8 *data, u32 size)
> +{
> + struct spi_message msg;
> + struct spi_transfer tx;
> + int ret = 0;
> +
> + if ((!spi) || (!data)) {
> + pr_err("%s: invalid arg\n", __func__);

The best would be to se dev_err() & friends for printing messages, as
they print the device's name as filled at struct device. If you don't use,
please add a define that will print the name at the logs, like:

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

either at the begining of the driver or at some header file.

Btw, I'm noticing that you're also using dev_err() on other places
of the code. Please standardize. OK, on a few places, you may still
need to use pr_err(), if you need to print a message before
initializing struct device, but I suspect that you can initialize
it before reading/writing to SPI.

> + return -EINVAL;
> + }
> +
> + memset(&tx, 0, sizeof(tx));
> + tx.tx_buf = data;
> + tx.len = size;
> +
> + spi_message_init(&msg);
> + spi_message_add_tail(&tx, &msg);
> + ret = spi_sync(spi, &msg);
> +
> + return ret;
> +}
> +
> +static int cxd2880_write_reg(struct spi_device *spi,
> + u8 subAddress, const u8 *data, u32 size)
> +{
> + u8 send_data[BURST_WRITE_MAX + 4];
> + const u8 *write_data_top = NULL;
> + int ret = 0;
> +
> + if ((!spi) || (!data)) {
> + pr_err("%s: invalid arg\n", __func__);
> + return -EINVAL;
> + }
> + if (size > BURST_WRITE_MAX) {
> + pr_err("%s: data size > WRITE_MAX\n", __func__);
> + return -EINVAL;
> + }
> +
> + if (subAddress + size > 0x100) {
> + pr_err("%s: out of range\n", __func__);
> + return -EINVAL;
> + }
> +
> + send_data[0] = 0x0E;
> + write_data_top = data;
> +
> + while (size > 0) {
> + send_data[1] = subAddress;
> + if (size > 255)
> + send_data[2] = 255;
> + else
> + send_data[2] = (u8)size;
> +
> + memcpy(&send_data[3], write_data_top, send_data[2]);
> +
> + ret = cxd2880_write_spi(spi, send_data, send_data[2] + 3);
> + if (ret) {
> + dev_err(&spi->dev, "%s: write spi failed %d\n",
> + __func__, ret);
> + break;
> + }
> + subAddress += send_data[2];
> + write_data_top += send_data[2];
> + size -= send_data[2];
> + }
> +
> + return ret;
> +}
> +
> +static int cxd2880_spi_read_ts(struct spi_device *spi,
> + u8 *read_data,
> + u32 packet_num)
> +{
> + int ret = 0;
> + u8 data[3];
> + struct spi_message message;
> + struct spi_transfer transfer[2];
> +
> + if ((!spi) || (!read_data) || (!packet_num)) {
> + pr_err("%s: invalid arg\n", __func__);
> + return -EINVAL;
> + }
> + if (packet_num > 0xFFFF) {
> + dev_err(&spi->dev, "%s: packet num > 0xFFFF\n", __func__);
> + return -EINVAL;
> + }
> +
> + data[0] = 0x10;
> + data[1] = (u8)((packet_num >> 8) & 0xFF);
> + data[2] = (u8)(packet_num & 0xFF);

Don't need to cast to (u8). We only use casts when needed at the Kernel
coding style.

> +
> + spi_message_init(&message);
> + memset(transfer, 0, sizeof(transfer));
> +
> + transfer[0].len = 3;
> + transfer[0].tx_buf = data;
> + spi_message_add_tail(&transfer[0], &message);
> + transfer[1].len = packet_num * 188;
> + transfer[1].rx_buf = read_data;
> + spi_message_add_tail(&transfer[1], &message);
> +
> + ret = spi_sync(spi, &message);
> + if (ret)
> + dev_err(&spi->dev, "%s: spi_write_then_read failed\n",
> + __func__);
> +
> + return ret;
> +}
> +
> +static int cxd2880_spi_read_ts_buffer_info(struct spi_device *spi,
> + struct cxd2880_ts_buf_info *info)
> +{
> + u8 send_data = 0x20;
> + u8 recv_data[2];
> + int ret = 0;
> +
> + if ((!spi) || (!info)) {
> + pr_err("%s: invalid arg\n", __func__);
> + return -EINVAL;
> + }
> +
> + ret = spi_write_then_read(spi, &send_data, 1,
> + recv_data, sizeof(recv_data));
> + if (ret)
> + dev_err(&spi->dev,
> + "%s: spi_write_then_read failed\n", __func__);
> +
> + info->read_ready = (u8)((recv_data[0] & 0x80) ? 1 : 0);
> + info->almost_full = (u8)((recv_data[0] & 0x40) ? 1 : 0);
> + info->almost_empty = (u8)((recv_data[0] & 0x20) ? 1 : 0);
> + info->overflow = (u8)((recv_data[0] & 0x10) ? 1 : 0);
> + info->underflow = (u8)((recv_data[0] & 0x08) ? 1 : 0);
> + info->packet_num = (u16)(((recv_data[0] & 0x07) << 8) | recv_data[1]);

Again, no need to cast.

> +
> + return ret;
> +}
> +
> +static int cxd2880_spi_clear_ts_buffer(struct spi_device *spi)
> +{
> + u8 data = 0x03;
> + int ret = 0;
> +
> + ret = cxd2880_write_spi(spi, &data, 1);
> +
> + if (ret)
> + pr_err("%s: write spi failed\n", __func__);
> +
> + return ret;
> +}
> +
> +static int cxd2880_set_pid_filter(struct spi_device *spi,
> + struct cxd2880_pid_filter_config *cfg)
> +{
> + u8 data[65];
> +
> + if (!spi) {
> + pr_err("%s: ivnalid arg\n", __func__);
> + return -EINVAL;
> + }
> +
> + data[0] = 0x00;
> + if (cxd2880_write_reg(spi, 0x00, &data[0], 1) != 0)
> + return -EIO;
> + if (!cfg) {
> + data[0] = 0x02;
> + if (cxd2880_write_reg(spi, 0x50, &data[0], 1) != 0)
> + return -EIO;
> + } else {
> + data[0] = (u8)(cfg->is_negative ? 0x01 : 0x00);
> + {
> + int i = 0;
> + u16 pid = 0;
> +
> + for (i = 0; i < CXD2880_MAX_FILTER_SIZE; i++) {
> + pid = cfg->pid_config[i].pid;
> + if (cfg->pid_config[i].is_enable) {
> + data[1 + (i * 2)] =
> + (u8)((u8)(pid >> 8) | 0x20);
> + data[2 + (i * 2)] =
> + (u8)(pid & 0xFF);
> + } else {
> + data[1 + (i * 2)] = 0x00;
> + data[2 + (i * 2)] = 0x00;
> + }
> + }
> + }
> + if (cxd2880_write_reg(spi, 0x50, data, 65) != 0)
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +static int cxd2880_update_pid_filter(struct cxd2880_dvb_spi *dvb_spi,
> + struct cxd2880_pid_filter_config *cfg,
> + bool is_all_pid_filter)
> +{
> + int ret = 0;
> +
> + if ((!dvb_spi) || (!cfg)) {
> + pr_err("%s: invalid arg.\n", __func__);
> + return -EINVAL;
> + }
> +
> + mutex_lock(&dvb_spi->spi_mutex);
> + if (is_all_pid_filter) {
> + struct cxd2880_pid_filter_config tmpcfg;
> +
> + memset(&tmpcfg, 0, sizeof(tmpcfg));
> + tmpcfg.is_negative = 1;
> + tmpcfg.pid_config[0].is_enable = 1;
> + tmpcfg.pid_config[0].pid = 0x1FFF;
> +
> + ret = cxd2880_set_pid_filter(dvb_spi->spi, &tmpcfg);
> + } else {
> + ret = cxd2880_set_pid_filter(dvb_spi->spi, cfg);
> + }
> + mutex_unlock(&dvb_spi->spi_mutex);
> +
> + if (ret) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: set_pid_filter failed\n", __func__);
> + }
> +
> + return ret;
> +}
> +
> +static int cxd2880_ts_read(void *arg)
> +{
> + struct cxd2880_dvb_spi *dvb_spi = NULL;
> + struct cxd2880_ts_buf_info info;
> + struct timespec ts;
> + long elapsed = 0;
> + long starttime = 0;
> + u32 i;
> + int ret;
> +
> + dvb_spi = (struct cxd2880_dvb_spi *)arg;
> + if (!dvb_spi) {
> + pr_err("%s: invalid arg\n", __func__);
> + return -EINVAL;
> + }
> +
> + ret = cxd2880_spi_clear_ts_buffer(dvb_spi->spi);
> + if (ret) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: set_clear_ts_buffer failed\n", __func__);
> + return ret;
> + }
> +
> + getnstimeofday(&getnstimeofdayts);
> + starttime = (ts.tv_sec * 1000) + (ts.tv_nsec / 1000000);

It is usually a very bad idea to use gettimeofday(), as this returns
a non-monotonic timestamp - e. g. if the wall clock is adjusted, it
can affect it. Also, it is slow. I suspect that the same is true for
getnstimeofday().

Anyway, as all you want to do here is to implement a timeout, you should use
jiffies instead, and macros to compare time with jiffies, e. g. something like
(from em28xx driver):

unsigned long timeout = jiffies + msecs_to_jiffies(EM28XX_I2C_XFER_TIMEOUT);

/* wait for completion */
while (time_is_after_jiffies(timeout)) {
ret = dev->em28xx_read_reg(dev, 0x05);
if (ret == 0x80 + len - 1)
return len;
if (ret == 0x94 + len - 1) {
dprintk(1, "R05 returned 0x%02x: I2C ACK error\n", ret);
return -ENXIO;
}
if (ret < 0) {
dev_warn(&dev->intf->dev,
"failed to get i2c transfer status from bridge register (error=%i)\n",
ret);
return ret;
}
msleep(5);
}

> + while (!kthread_should_stop()) {
> + getnstimeofday(&ts);
> + elapsed =
> + ((ts.tv_sec * 1000) + (ts.tv_nsec / 1000000))
> + - starttime;
> + ret = cxd2880_spi_read_ts_buffer_info(dvb_spi->spi,
> + &info);
> + if (ret) {
> + pr_err("%s: spi_read_ts_buffer_info error\n",
> + __func__);
> + return ret;
> + }
> +
> + if (info.packet_num > MAX_TRANS_PACKET) {
> + for (i = 0; i < info.packet_num / MAX_TRANS_PACKET;
> + i++) {
> + cxd2880_spi_read_ts(dvb_spi->spi,
> + dvb_spi->ts_buf,
> + MAX_TRANS_PACKET);
> + dvb_dmx_swfilter(&dvb_spi->demux,
> + dvb_spi->ts_buf,
> + MAX_TRANS_PACKET * 188);
> + }
> + starttime = (ts.tv_sec * 1000) + (ts.tv_nsec / 1000000);
> + } else if ((info.packet_num > 0) && (elapsed >= 500)) {
> + cxd2880_spi_read_ts(dvb_spi->spi,
> + dvb_spi->ts_buf,
> + info.packet_num);
> + dvb_dmx_swfilter(&dvb_spi->demux,
> + dvb_spi->ts_buf,
> + info.packet_num * 188);
> + starttime = (ts.tv_sec * 1000) + (ts.tv_nsec / 1000000);
> + } else {
> + usleep_range(10000, 11000);
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int cxd2880_start_feed(struct dvb_demux_feed *feed)
> +{
> + int ret = 0;
> + int i = 0;
> + struct dvb_demux *demux = NULL;
> + struct cxd2880_dvb_spi *dvb_spi = NULL;
> +
> + if (!feed) {
> + pr_err("%s: invalid arg\n", __func__);
> + return -EINVAL;
> + }
> +
> + demux = feed->demux;
> + if (!demux) {
> + pr_err("%s: feed->demux is NULL\n", __func__);
> + return -EINVAL;
> + }
> + dvb_spi = (struct cxd2880_dvb_spi *)demux->priv;
> +
> + if (dvb_spi->feed_count == CXD2880_MAX_FILTER_SIZE) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: Exceeded maximum PID count (32).", __func__);
> + dev_err(&dvb_spi->spi->dev,
> + "Selected PID cannot be enabled.\n");
> + return -EBUSY;
> + }
> +
> + if (feed->pid == 0x2000) {
> + if (dvb_spi->all_pid_feed_count == 0) {
> + ret = cxd2880_update_pid_filter(dvb_spi,
> + &dvb_spi->filter_config,
> + true);
> + if (ret) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: update pid filter failed\n",
> + __func__);
> + return ret;
> + }
> + }
> + dvb_spi->all_pid_feed_count++;
> +
> + dev_dbg(&dvb_spi->spi->dev,
> + "%s: all PID feed (count = %d)\n",
> + __func__, dvb_spi->all_pid_feed_count);
> + } else {
> + struct cxd2880_pid_filter_config cfgtmp;
> +
> + cfgtmp = dvb_spi->filter_config;
> +
> + for (i = 0; i < CXD2880_MAX_FILTER_SIZE; i++) {
> + if (cfgtmp.pid_config[i].is_enable == 0) {
> + cfgtmp.pid_config[i].is_enable = 1;
> + cfgtmp.pid_config[i].pid = feed->pid;
> + dev_dbg(&dvb_spi->spi->dev,
> + "%s: store PID %d to #%d\n",
> + __func__, feed->pid, i);
> + break;
> + }
> + }
> + if (i == CXD2880_MAX_FILTER_SIZE) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: PID filter is full. Assumed bug.\n",
> + __func__);
> + return -EBUSY;
> + }
> + if (!dvb_spi->all_pid_feed_count)
> + ret = cxd2880_update_pid_filter(dvb_spi,
> + &cfgtmp,
> + false);
> + if (ret)
> + return ret;
> +
> + dvb_spi->filter_config = cfgtmp;
> + }
> +
> + if (dvb_spi->feed_count == 0) {
> + dvb_spi->ts_buf =
> + kmalloc(sizeof(u8) * MAX_TRANS_PACKET * 188,
> + GFP_KERNEL | GFP_DMA);

nitpick: no need for sizeof(u8)

> + if (!dvb_spi->ts_buf) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: ts buffer allocate failed\n", __func__);
> + memset(&dvb_spi->filter_config, 0,
> + sizeof(dvb_spi->filter_config));
> + dvb_spi->all_pid_feed_count = 0;
> + return -ENOMEM;
> + }
> + dvb_spi->cxd2880_ts_read_thread = kthread_run(cxd2880_ts_read,
> + dvb_spi,
> + "cxd2880_ts_read");

nitpick: please adjust the alignment here (and on similar places) to
match the open parenthesis, e. g.:

dvb_spi->cxd2880_ts_read_thread = kthread_run(cxd2880_ts_read,
dvb_spi,
"cxd2880_ts_read");


> + if (IS_ERR(dvb_spi->cxd2880_ts_read_thread)) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: kthread_run failed/\n",
> + __func__);
> + kfree(dvb_spi->ts_buf);
> + dvb_spi->ts_buf = NULL;
> + memset(&dvb_spi->filter_config, 0,
> + sizeof(dvb_spi->filter_config));
> + dvb_spi->all_pid_feed_count = 0;
> + return PTR_ERR(dvb_spi->cxd2880_ts_read_thread);
> + }
> + }
> +
> + dvb_spi->feed_count++;
> +
> + dev_dbg(&dvb_spi->spi->dev, "%s: start feed (count %d)\n",
> + __func__, dvb_spi->feed_count);
> + return 0;
> +}
> +
> +static int cxd2880_stop_feed(struct dvb_demux_feed *feed)
> +{
> + int i = 0;
> + int ret = 0;
> + struct dvb_demux *demux = NULL;
> + struct cxd2880_dvb_spi *dvb_spi = NULL;
> +
> + if (!feed) {
> + pr_err("%s: invalid arg\n", __func__);
> + return -EINVAL;
> + }
> +
> + demux = feed->demux;
> + if (!demux) {
> + pr_err("%s: feed->demux is NULL\n", __func__);
> + return -EINVAL;
> + }
> + dvb_spi = (struct cxd2880_dvb_spi *)demux->priv;
> +
> + if (!dvb_spi->feed_count) {
> + dev_warn(&dvb_spi->spi->dev,
> + "%s: no feed is started\n", __func__);
> + return -EINVAL;
> + }
> +
> + if (feed->pid == 0x2000) {
> + /*
> + * Special PID case.
> + * Number of 0x2000 feed request was stored
> + * in dvb_spi->all_pid_feed_count.
> + */
> + if (dvb_spi->all_pid_feed_count <= 0) {
> + dev_warn(&dvb_spi->spi->dev,
> + "%s: PID %d not found.\n",
> + __func__, feed->pid);
> + return -EINVAL;
> + }
> + dvb_spi->all_pid_feed_count--;
> + } else {
> + struct cxd2880_pid_filter_config cfgtmp;
> +
> + cfgtmp = dvb_spi->filter_config;
> +
> + for (i = 0; i < CXD2880_MAX_FILTER_SIZE; i++) {
> + if (feed->pid == cfgtmp.pid_config[i].pid &&
> + cfgtmp.pid_config[i].is_enable != 0) {
> + cfgtmp.pid_config[i].is_enable = 0;
> + cfgtmp.pid_config[i].pid = 0;
> + dev_dbg(&dvb_spi->spi->dev,
> + "%s: removed PID %d from #%d\n",
> + __func__, feed->pid, i);
> + break;
> + }
> + }
> + dvb_spi->filter_config = cfgtmp;
> +
> + if (i == CXD2880_MAX_FILTER_SIZE) {
> + dev_warn(&dvb_spi->spi->dev, "%s: PID %d not found\n",
> + __func__, feed->pid);
> + return -EINVAL;
> + }
> + }
> +
> + ret = cxd2880_update_pid_filter(dvb_spi,
> + &dvb_spi->filter_config,
> + dvb_spi->all_pid_feed_count > 0);
> + dvb_spi->feed_count--;
> +
> + if (dvb_spi->feed_count == 0) {
> + int ret_stop = 0;
> +
> + ret_stop = kthread_stop(dvb_spi->cxd2880_ts_read_thread);
> + if (ret_stop) {
> + dev_err(&dvb_spi->spi->dev,
> + "%s: cxd2880_ts_read thread didn't terminate normally\n",
> + __func__);
> + ret = ret_stop;
> + }
> + kfree(dvb_spi->ts_buf);
> + dvb_spi->ts_buf = NULL;
> + }
> +
> + dev_dbg(&dvb_spi->spi->dev, "%s: stop feed ok.(count %d)\n",
> + __func__, dvb_spi->feed_count);
> +
> + return ret;
> +}
> +
> +static const struct of_device_id cxd2880_spi_of_match[] = {
> + { .compatible = "sony,cxd2880" },
> + { /* sentinel */ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, cxd2880_spi_of_match);
> +
> +static int
> +cxd2880_spi_probe(struct spi_device *spi)
> +{
> + int ret = 0;
> + struct cxd2880_dvb_spi *dvb_spi = NULL;
> + struct cxd2880_config config;
> +
> + if (!spi) {
> + pr_err("%s: invalid arg.\n", __func__);
> + return -EINVAL;
> + }
> +
> + dvb_spi = kzalloc(sizeof(struct cxd2880_dvb_spi), GFP_KERNEL);
> + if (!dvb_spi)
> + return -ENOMEM;
> +
> + dvb_spi->spi = spi;
> + mutex_init(&dvb_spi->spi_mutex);
> + dev_set_drvdata(&spi->dev, dvb_spi);
> + config.spi = spi;
> + config.spi_mutex = &dvb_spi->spi_mutex;
> +
> + ret = dvb_register_adapter(&dvb_spi->adapter,
> + "CXD2880",
> + THIS_MODULE,
> + &spi->dev,
> + adapter_nr);
> + if (ret < 0) {
> + dev_err(&spi->dev, "%s: dvb_register_adapter() failed\n",
> + __func__);
> + goto fail_adapter;
> + }
> +
> + if (!dvb_attach(cxd2880_attach, &dvb_spi->dvb_fe, &config)) {
> + dev_err(&spi->dev, "%s: cxd2880_attach failed\n", __func__);
> + goto fail_attach;
> + }
> +
> + ret = dvb_register_frontend(&dvb_spi->adapter,
> + &dvb_spi->dvb_fe);
> + if (ret < 0) {
> + dev_err(&spi->dev, "%s: dvb_register_frontend() failed\n",
> + __func__);
> + goto fail_frontend;
> + }
> +
> + dvb_spi->demux.dmx.capabilities = DMX_TS_FILTERING;
> + dvb_spi->demux.priv = dvb_spi;
> + dvb_spi->demux.filternum = CXD2880_MAX_FILTER_SIZE;
> + dvb_spi->demux.feednum = CXD2880_MAX_FILTER_SIZE;
> + dvb_spi->demux.start_feed = cxd2880_start_feed;
> + dvb_spi->demux.stop_feed = cxd2880_stop_feed;
> +
> + ret = dvb_dmx_init(&dvb_spi->demux);
> + if (ret < 0) {
> + dev_err(&spi->dev, "%s: dvb_dmx_init() failed\n", __func__);
> + goto fail_dmx;
> + }
> +
> + dvb_spi->dmxdev.filternum = CXD2880_MAX_FILTER_SIZE;
> + dvb_spi->dmxdev.demux = &dvb_spi->demux.dmx;
> + dvb_spi->dmxdev.capabilities = 0;
> + ret = dvb_dmxdev_init(&dvb_spi->dmxdev,
> + &dvb_spi->adapter);
> + if (ret < 0) {
> + dev_err(&spi->dev, "%s: dvb_dmxdev_init() failed\n", __func__);
> + goto fail_dmxdev;
> + }
> +
> + dvb_spi->dmx_fe.source = DMX_FRONTEND_0;
> + ret = dvb_spi->demux.dmx.add_frontend(&dvb_spi->demux.dmx,
> + &dvb_spi->dmx_fe);
> + if (ret < 0) {
> + dev_err(&spi->dev, "%s: add_frontend() failed\n", __func__);
> + goto fail_dmx_fe;
> + }
> +
> + ret = dvb_spi->demux.dmx.connect_frontend(&dvb_spi->demux.dmx,
> + &dvb_spi->dmx_fe);
> + if (ret < 0) {
> + dev_err(&spi->dev, "%s: dvb_register_frontend() failed\n",
> + __func__);
> + goto fail_fe_conn;
> + }
> +
> + dev_info(&spi->dev, "Sony CXD2880 has successfully attached.\n");
> +
> + return 0;
> +
> +fail_fe_conn:
> + dvb_spi->demux.dmx.remove_frontend(&dvb_spi->demux.dmx,
> + &dvb_spi->dmx_fe);
> +fail_dmx_fe:
> + dvb_dmxdev_release(&dvb_spi->dmxdev);
> +fail_dmxdev:
> + dvb_dmx_release(&dvb_spi->demux);
> +fail_dmx:
> + dvb_unregister_frontend(&dvb_spi->dvb_fe);
> +fail_frontend:
> + dvb_frontend_detach(&dvb_spi->dvb_fe);
> +fail_attach:
> + dvb_unregister_adapter(&dvb_spi->adapter);
> +fail_adapter:
> + kfree(dvb_spi);
> + return ret;
> +}
> +
> +static int
> +cxd2880_spi_remove(struct spi_device *spi)
> +{
> + struct cxd2880_dvb_spi *dvb_spi;
> +
> + if (!spi) {
> + pr_err("%s: invalid arg\n", __func__);
> + return -EINVAL;
> + }
> +
> + dvb_spi = (struct cxd2880_dvb_spi *)dev_get_drvdata(&spi->dev);

No need to cast.

> +
> + if (!dvb_spi) {
> + pr_err("%s: failed\n", __func__);
> + return -EINVAL;
> + }
> + dvb_spi->demux.dmx.remove_frontend(&dvb_spi->demux.dmx,
> + &dvb_spi->dmx_fe);
> + dvb_dmxdev_release(&dvb_spi->dmxdev);
> + dvb_dmx_release(&dvb_spi->demux);
> + dvb_unregister_frontend(&dvb_spi->dvb_fe);
> + dvb_frontend_detach(&dvb_spi->dvb_fe);
> + dvb_unregister_adapter(&dvb_spi->adapter);
> +
> + kfree(dvb_spi);
> + dev_info(&spi->dev, "%s: cxd2880_spi remove ok.\n", __func__);
> +
> + return 0;
> +}
> +
> +static const struct spi_device_id cxd2880_spi_id[] = {
> + { "cxd2880", 0 },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(spi, cxd2880_spi_id);
> +
> +static struct spi_driver cxd2880_spi_driver = {
> + .driver = {
> + .name = "cxd2880",
> + .of_match_table = cxd2880_spi_of_match,
> + },
> + .id_table = cxd2880_spi_id,
> + .probe = cxd2880_spi_probe,
> + .remove = cxd2880_spi_remove,
> +};
> +module_spi_driver(cxd2880_spi_driver);
> +
> +MODULE_DESCRIPTION(
> +"Sony CXD2880 DVB-T2/T tuner + demodulator drvier SPI adapter");
> +MODULE_AUTHOR("Sony Semiconductor Solutions Corporation");
> +MODULE_LICENSE("GPL v2");



Thanks,
Mauro