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Groups > linux.kernel > #1659213
| From | Christopher Bostic <cbostic@linux.vnet.ibm.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH v8 05/24] drivers/fsi: Add slave & master read/write APIs |
| Date | 2017-06-06 23:10 +0200 |
| Message-ID | <tPtTI-5H7-19@gated-at.bofh.it> (permalink) |
| References | <tPtTH-5H7-1@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
From: Jeremy Kerr <jk@ozlabs.org>
Introduce functions to perform reads/writes on the slave address space;
these simply pass the request on the slave's master with the correct
link and slave ID.
We implement these on top of similar helpers for the master.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com>
---
drivers/fsi/fsi-core.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 92 insertions(+)
diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
index e90d45d..1ec9790 100644
--- a/drivers/fsi/fsi-core.c
+++ b/drivers/fsi/fsi-core.c
@@ -32,7 +32,64 @@ struct fsi_slave {
#define to_fsi_slave(d) container_of(d, struct fsi_slave, dev)
+static int fsi_master_read(struct fsi_master *master, int link,
+ uint8_t slave_id, uint32_t addr, void *val, size_t size);
+static int fsi_master_write(struct fsi_master *master, int link,
+ uint8_t slave_id, uint32_t addr, const void *val, size_t size);
+
/* FSI slave support */
+static int fsi_slave_calc_addr(struct fsi_slave *slave, uint32_t *addrp,
+ uint8_t *idp)
+{
+ uint32_t addr = *addrp;
+ uint8_t id = *idp;
+
+ if (addr > slave->size)
+ return -EINVAL;
+
+ /* For 23 bit addressing, we encode the extra two bits in the slave
+ * id (and the slave's actual ID needs to be 0).
+ */
+ if (addr > 0x1fffff) {
+ if (slave->id != 0)
+ return -EINVAL;
+ id = (addr >> 21) & 0x3;
+ addr &= 0x1fffff;
+ }
+
+ *addrp = addr;
+ *idp = id;
+ return 0;
+}
+
+static int fsi_slave_read(struct fsi_slave *slave, uint32_t addr,
+ void *val, size_t size)
+{
+ uint8_t id = slave->id;
+ int rc;
+
+ rc = fsi_slave_calc_addr(slave, &addr, &id);
+ if (rc)
+ return rc;
+
+ return fsi_master_read(slave->master, slave->link, id,
+ addr, val, size);
+}
+
+static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
+ const void *val, size_t size)
+{
+ uint8_t id = slave->id;
+ int rc;
+
+ rc = fsi_slave_calc_addr(slave, &addr, &id);
+ if (rc)
+ return rc;
+
+ return fsi_master_write(slave->master, slave->link, id,
+ addr, val, size);
+}
+
static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id)
{
/* todo: initialise slave device, perform engine scan */
@@ -41,6 +98,41 @@ static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id)
}
/* FSI master support */
+static int fsi_check_access(uint32_t addr, size_t size)
+{
+ if (size != 1 && size != 2 && size != 4)
+ return -EINVAL;
+
+ if ((addr & 0x3) != (size & 0x3))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int fsi_master_read(struct fsi_master *master, int link,
+ uint8_t slave_id, uint32_t addr, void *val, size_t size)
+{
+ int rc;
+
+ rc = fsi_check_access(addr, size);
+ if (rc)
+ return rc;
+
+ return master->read(master, link, slave_id, addr, val, size);
+}
+
+static int fsi_master_write(struct fsi_master *master, int link,
+ uint8_t slave_id, uint32_t addr, const void *val, size_t size)
+{
+ int rc;
+
+ rc = fsi_check_access(addr, size);
+ if (rc)
+ return rc;
+
+ return master->write(master, link, slave_id, addr, val, size);
+}
+
static int fsi_master_scan(struct fsi_master *master)
{
int link;
--
1.8.2.2
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[PATCH v8 00/24] FSI device driver implementation Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:10 +0200 [PATCH v8 06/24] drivers/fsi: Set up links for slave communication Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:10 +0200 [PATCH v8 01/24] drivers/fsi: Add fsi master definition Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:10 +0200 [PATCH v8 11/24] drivers/fsi: Add master unscan Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:10 +0200 [PATCH v8 05/24] drivers/fsi: Add slave & master read/write APIs Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:10 +0200 [PATCH v8 04/24] lib: Add crc4 module Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:10 +0200 [PATCH v8 12/24] drivers/fsi: Add documentation for GPIO bindings Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 24/24] drivers/fsi: Add module license to core driver Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 19/24] drivers/fsi: Add GPIO based FSI master Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 14/24] drivers/fsi: Add sysfs files for FSI master & slave accesses Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 20/24] drivers/fsi/gpio: Add tracepoints for GPIO master Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 22/24] drivers/fsi: Add hub master support Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 17/24] drivers/fsi: Add error handling for slave Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 16/24] drivers/fsi: Add tracepoints for low-level operations Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 10/24] drivers/fsi: Add device read/write/peek API Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 21/24] drivers/fsi: Add SCOM FSI client device driver Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 18/24] drivers/fsi: Document FSI master sysfs files in ABI Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 08/24] drivers/fsi: Set slave SMODE to init communication Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 15/24] drivers/fsi: expose direct-access slave API Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 07/24] drivers/fsi: Implement slave initialisation Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 02/24] drivers/fsi: Add slave definition Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 13/24] drivers/fsi: Add client driver register utilities Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 23/24] drivers/fsi: Use asynchronous slave mode Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 03/24] drivers/fsi: Add empty master scan Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200 [PATCH v8 09/24] drivers/fsi: scan slaves & register devices Christopher Bostic <cbostic@linux.vnet.ibm.com> - 2017-06-06 23:20 +0200
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