diff options
author | Stefan Wahren <stefan.wahren@i2se.com> | 2018-09-24 13:20:10 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2018-09-24 12:26:06 -0700 |
commit | 48c1699ec298dd9fbcdcac4fd63ec6db2bd5cc84 (patch) | |
tree | 3c70b5d658daf2b02bfae32ba2190df0e9943653 /drivers/net/ethernet/qualcomm/qca_7k.c | |
parent | 4128c0cfb1d74cb1fa2a2fb6824348b349d30f04 (diff) | |
download | linux-48c1699ec298dd9fbcdcac4fd63ec6db2bd5cc84.tar.bz2 |
net: qca_spi: Introduce write register verification
The SPI protocol for the QCA7000 doesn't have any fault detection.
In order to increase the drivers reliability in noisy environments,
we could implement a write verification inspired by the enc28j60.
This should avoid situations were the driver wrongly assumes the
receive interrupt is enabled and miss all incoming packets.
This function is disabled per default and can be controlled via module
parameter wr_verify.
Signed-off-by: Michael Heimpold <michael.heimpold@i2se.com>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/qualcomm/qca_7k.c')
-rw-r--r-- | drivers/net/ethernet/qualcomm/qca_7k.c | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/drivers/net/ethernet/qualcomm/qca_7k.c b/drivers/net/ethernet/qualcomm/qca_7k.c index 6c8543fb90c0..4292c89bd35c 100644 --- a/drivers/net/ethernet/qualcomm/qca_7k.c +++ b/drivers/net/ethernet/qualcomm/qca_7k.c @@ -81,8 +81,8 @@ qcaspi_read_register(struct qcaspi *qca, u16 reg, u16 *result) return ret; } -int -qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value) +static int +__qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value) { __be16 tx_data[2]; struct spi_transfer transfer[2]; @@ -117,3 +117,33 @@ qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value) return ret; } + +int +qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value, int retry) +{ + int ret, i = 0; + u16 confirmed; + + do { + ret = __qcaspi_write_register(qca, reg, value); + if (ret) + return ret; + + if (!retry) + return 0; + + ret = qcaspi_read_register(qca, reg, &confirmed); + if (ret) + return ret; + + ret = confirmed != value; + if (!ret) + return 0; + + i++; + qca->stats.write_verify_failed++; + + } while (i <= retry); + + return ret; +} |