lkml.org 
[lkml]   [2017]   [May]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v6 07/23] drivers/fsi: Implement slave initialisation
From
Date


On 5/2/17 1:24 AM, Joel Stanley wrote:
> On Tue, Apr 11, 2017 at 5:16 AM, Christopher Bostic
> <cbostic@linux.vnet.ibm.com> wrote:
>> From: Jeremy Kerr <jk@ozlabs.org>
>>
>> Implement fsi_slave_init: if we can read a chip ID, create fsi_slave
>> devices and register with the driver core.
>>
>> Includes changes from Chris Bostic <cbostic@linux.vnet.ibm.com>.
>>
>> Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
>> Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com>
>> Signed-off-by: Joel Stanley <joel@jms.id.au>
>> ---
>> drivers/fsi/fsi-core.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++--
>> 1 file changed, 64 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
>> index 6e1cfdf..c705ca2 100644
>> --- a/drivers/fsi/fsi-core.c
>> +++ b/drivers/fsi/fsi-core.c
>> @@ -17,9 +17,12 @@
>> #include <linux/fsi.h>
>> #include <linux/idr.h>
>> #include <linux/module.h>
>> +#include <linux/slab.h>
>>
>> #include "fsi-master.h"
>>
>> +#define FSI_SLAVE_SIZE_23b 0x800000
>> +
>> static DEFINE_IDA(master_ida);
>>
>> struct fsi_slave {
>> @@ -114,11 +117,70 @@ static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
>> addr, val, size);
>> }
>>
>> +static void fsi_slave_release(struct device *dev)
>> +{
>> + struct fsi_slave *slave = to_fsi_slave(dev);
>> +
>> + kfree(slave);
>> +}
>> +
>> static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id)
>> {
>> - /* todo: initialise slave device, perform engine scan */
>> + struct fsi_slave *slave;
>> + uint32_t chip_id;
>> + uint8_t crc;
>> + int rc;
>> +
>> + /* Currently, we only support single slaves on a link, and use the
>> + * full 23-bit address range
>> + */
>> + if (id != 0)
>> + return -EINVAL;
>> +
>> + rc = fsi_master_read(master, link, id, 0, &chip_id, sizeof(chip_id));
>> + if (rc) {
>> + dev_warn(&master->dev, "can't read slave %02x:%02x %d\n",
>> + link, id, rc);
> When I boot a system with this driver loaded, I get his warning:
>
> [ 9.740000] usbhid: USB HID core driver
> [ 9.840000] fsi0: can't read slave 00:00 -5
> [ 9.840000] NET: Registered protocol family 10
>
> Two things:
>
> There's a space in front of "fsi0".

Hi Joel,

Will correct.
>
> This warning isn't useful at that point. The slave is not readable as
> the FSI master is not present (the P9 hasn't been turned on). Can we
> avoid printing the warning at boot?

Yes agreed. Will remove the warning in that case.

Thanks,
Chris
>
> Cheers,
>
> Joel
>
>> + return -ENODEV;
>> + }
>> + chip_id = be32_to_cpu(chip_id);
>> +
>> + crc = fsi_crc4(0, chip_id, 32);
>> + if (crc) {
>> + dev_warn(&master->dev, "slave %02x:%02x invalid chip id CRC!\n",
>> + link, id);
>> + return -EIO;
>> + }
>> +
>> + dev_info(&master->dev, "fsi: found chip %08x at %02x:%02x:%02x\n",
>> + chip_id, master->idx, link, id);
>> +
>> + /* We can communicate with a slave; create the slave device and
>> + * register.
>> + */
>> + slave = kzalloc(sizeof(*slave), GFP_KERNEL);
>> + if (!slave)
>> + return -ENOMEM;
>> +
>> + slave->master = master;
>> + slave->dev.parent = &master->dev;
>> + slave->dev.release = fsi_slave_release;
>> + slave->link = link;
>> + slave->id = id;
>> + slave->size = FSI_SLAVE_SIZE_23b;
>> +
>> + dev_set_name(&slave->dev, "slave@%02x:%02x", link, id);
>> + rc = device_register(&slave->dev);
>> + if (rc < 0) {
>> + dev_warn(&master->dev, "failed to create slave device: %d\n",
>> + rc);
>> + put_device(&slave->dev);
>> + return rc;
>> + }
>> +
>> + /* todo: perform engine scan */
>>
>> - return -ENODEV;
>> + return rc;
>> }
>>
>> /* FSI master support */
>> --
>> 1.8.2.2
>>

\
 
 \ /
  Last update: 2017-05-02 20:59    [W:0.137 / U:0.440 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site