| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.4 21/37] i2c: rcar: dont issue stop when HW does it automatically | Date | Tue, 5 Jun 2018 19:01:26 +0200 |
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4.4-stable review patch. If anyone has any objections, please let me know.
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From: Wolfram Sang <wsa+renesas@sang-engineering.com>
commit d89667b14f9d13b684287f6189ca209af5feee43 upstream.
The manual says (55.4.8.6) that HW does automatically send STOP after NACK was received. My measuerments confirm that.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com> Reviewed-by: Biju Das <biju.das@bp.renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/i2c/busses/i2c-rcar.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -455,8 +455,8 @@ static irqreturn_t rcar_i2c_irq(int irq, /* Nack */ if (msr & MNR) { - /* go to stop phase */ - rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP); + /* HW automatically sends STOP after received NACK */ + rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA); rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP); rcar_i2c_flags_set(priv, ID_NACK); goto out;
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