From mboxrd@z Thu Jan 1 00:00:00 1970 From: cbostic@linux.vnet.ibm.com (Christopher Bostic) Date: Tue, 4 Apr 2017 21:05:50 -0500 Subject: [PATCH v5 06/23] drivers/fsi: Set up links for slave communication In-Reply-To: <20170405020607.79939-1-cbostic@linux.vnet.ibm.com> References: <20170405020607.79939-1-cbostic@linux.vnet.ibm.com> Message-ID: <20170405020607.79939-7-cbostic@linux.vnet.ibm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Chris Bostic Enable each link and send a break command, and try to detect a slave by reading from the SMODE register. Signed-off-by: Chris Bostic Signed-off-by: Joel Stanley --- drivers/fsi/fsi-core.c | 37 +++++++++++++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-) diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c index 32698ed..6e1cfdf 100644 --- a/drivers/fsi/fsi-core.c +++ b/drivers/fsi/fsi-core.c @@ -157,12 +157,45 @@ static int fsi_master_write(struct fsi_master *master, int link, return master->write(master, link, slave_id, addr, val, size); } +static int fsi_master_link_enable(struct fsi_master *master, int link) +{ + if (master->link_enable) + return master->link_enable(master, link); + + return 0; +} + +/* + * Issue a break command on this link + */ +static int fsi_master_break(struct fsi_master *master, int link) +{ + if (master->send_break) + return master->send_break(master, link); + + return 0; +} + static int fsi_master_scan(struct fsi_master *master) { - int link; + int link, rc; + + for (link = 0; link < master->n_links; link++) { + rc = fsi_master_link_enable(master, link); + if (rc) { + dev_dbg(&master->dev, + "enable link %d failed: %d\n", link, rc); + continue; + } + rc = fsi_master_break(master, link); + if (rc) { + dev_dbg(&master->dev, + "break to link %d failed: %d\n", link, rc); + continue; + } - for (link = 0; link < master->n_links; link++) fsi_slave_init(master, link, 0); + } return 0; } -- 1.8.2.2