* [PATCH 0/2] Add support for AC timing adjustment @ 2019-06-11 8:11 Qii Wang 2019-06-11 8:11 ` [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding Qii Wang 2019-06-11 8:11 ` [PATCH 2/2] i2c: mediatek: Add i2c AC timing adjust support Qii Wang 0 siblings, 2 replies; 6+ messages in thread From: Qii Wang @ 2019-06-11 8:11 UTC (permalink / raw) To: wsa Cc: devicetree, qii.wang, srv_heupstream, leilk.liu, linux-kernel, robh+dt, linux-mediatek, linux-i2c, matthias.bgg, linux-arm-kernel This series are based on 5.2-rc1, we provide two patches to support AC timing adjustment. Qii Wang (2): dt-bindings: i2c: Add MediaTek i2c AC timing binding i2c: mediatek: Add i2c AC timing adjust support .../devicetree/bindings/i2c/i2c-mt65xx.txt | 11 +++ drivers/i2c/busses/i2c-mt65xx.c | 94 +++++++++++++++++--- 2 files changed, 93 insertions(+), 12 deletions(-) -- 1.7.9.5 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding 2019-06-11 8:11 [PATCH 0/2] Add support for AC timing adjustment Qii Wang @ 2019-06-11 8:11 ` Qii Wang 2019-06-26 13:39 ` Wolfram Sang 2019-06-11 8:11 ` [PATCH 2/2] i2c: mediatek: Add i2c AC timing adjust support Qii Wang 1 sibling, 1 reply; 6+ messages in thread From: Qii Wang @ 2019-06-11 8:11 UTC (permalink / raw) To: wsa Cc: devicetree, qii.wang, srv_heupstream, leilk.liu, linux-kernel, robh+dt, linux-mediatek, linux-i2c, matthias.bgg, linux-arm-kernel Add i2c AC timing binding to binding file. It can give the AC timing parameters to meet I2C specification at different speed. Signed-off-by: Qii Wang <qii.wang@mediatek.com> --- .../devicetree/bindings/i2c/i2c-mt65xx.txt | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt index 68f6d73..0f92813 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt @@ -30,6 +30,7 @@ Optional properties: - mediatek,have-pmic: platform can control i2c form special pmic side. Only mt6589 and mt8135 support this feature. - mediatek,use-push-pull: IO config use push-pull mode. + - ac-timing: give some AC timing parameters to meet i2c spec fully. Example: @@ -43,5 +44,15 @@ Example: clock-div = <16>; clocks = <&i2c0_ck>, <&ap_dma_ck>; clock-names = "main", "dma"; + ac-timing = /bits/ 16 < + 0x8001 /* 0:ext */ + 0x0005 /* 1:inter_clk_div */ + 0x0102 /* 2:scl_hl_ratio */ + 0x0102 /* 3:hs_scl_hl_ratio */ + 0x0002 /* 4:scl_mis_comp */ + 0x0002 /* 5:sta_stop */ + 0x0002 /* 6:hs_sta_stop */ + 0x0002 /* 7:sda_timing */ + >; }; -- 1.7.9.5 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding 2019-06-11 8:11 ` [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding Qii Wang @ 2019-06-26 13:39 ` Wolfram Sang 2019-07-17 12:55 ` Qii Wang 0 siblings, 1 reply; 6+ messages in thread From: Wolfram Sang @ 2019-06-26 13:39 UTC (permalink / raw) To: Qii Wang Cc: devicetree, srv_heupstream, leilk.liu, linux-kernel, robh+dt, linux-mediatek, linux-i2c, matthias.bgg, linux-arm-kernel [-- Attachment #1.1: Type: text/plain, Size: 1109 bytes --] Hi, On Tue, Jun 11, 2019 at 04:11:54PM +0800, Qii Wang wrote: > Add i2c AC timing binding to binding file. It can give the AC > timing parameters to meet I2C specification at different speed. > > Signed-off-by: Qii Wang <qii.wang@mediatek.com> I think this is a too specific 1:1 mapping of your register set into DT world. We already have these generic parameters: - clock-frequency frequency of bus clock in Hz. - i2c-scl-falling-time-ns Number of nanoseconds the SCL signal takes to fall; t(f) in the I2C specification. - i2c-scl-internal-delay-ns Number of nanoseconds the IP core additionally needs to setup SCL. - i2c-scl-rising-time-ns Number of nanoseconds the SCL signal takes to rise; t(r) in the I2C specification. - i2c-sda-falling-time-ns Number of nanoseconds the SDA signal takes to fall; t(f) in the I2C specification. (check Documentation/devicetree/bindings/i2c/i2c.txt) Can't you use those to derive your values from that? Which ones are you missing if not? Regards, Wolfram [-- Attachment #1.2: signature.asc --] [-- Type: application/pgp-signature, Size: 833 bytes --] [-- Attachment #2: Type: text/plain, Size: 176 bytes --] _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding 2019-06-26 13:39 ` Wolfram Sang @ 2019-07-17 12:55 ` Qii Wang 2019-07-17 13:29 ` Wolfram Sang 0 siblings, 1 reply; 6+ messages in thread From: Qii Wang @ 2019-07-17 12:55 UTC (permalink / raw) To: Wolfram Sang Cc: devicetree, srv_heupstream, leilk.liu, linux-kernel, robh+dt, linux-mediatek, linux-i2c, matthias.bgg, linux-arm-kernel On Wed, 2019-06-26 at 15:39 +0200, Wolfram Sang wrote: > Hi, > > On Tue, Jun 11, 2019 at 04:11:54PM +0800, Qii Wang wrote: > > Add i2c AC timing binding to binding file. It can give the AC > > timing parameters to meet I2C specification at different speed. > > > > Signed-off-by: Qii Wang <qii.wang@mediatek.com> > > I think this is a too specific 1:1 mapping of your register set into DT > world. We already have these generic parameters: > > - clock-frequency > frequency of bus clock in Hz. > > - i2c-scl-falling-time-ns > Number of nanoseconds the SCL signal takes to fall; t(f) in the I2C > specification. > > - i2c-scl-internal-delay-ns > Number of nanoseconds the IP core additionally needs to setup SCL. > > - i2c-scl-rising-time-ns > Number of nanoseconds the SCL signal takes to rise; t(r) in the I2C > specification. > > - i2c-sda-falling-time-ns > Number of nanoseconds the SDA signal takes to fall; t(f) in the I2C > specification. > > (check Documentation/devicetree/bindings/i2c/i2c.txt) > > Can't you use those to derive your values from that? Which ones are you missing > if not? > > Regards, > > Wolfram I have take a little time to develop a new patch which based on your suggestions, and it tested OK. Thanks for your suggestions, I will update the patch after I test it fully. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding 2019-07-17 12:55 ` Qii Wang @ 2019-07-17 13:29 ` Wolfram Sang 0 siblings, 0 replies; 6+ messages in thread From: Wolfram Sang @ 2019-07-17 13:29 UTC (permalink / raw) To: Qii Wang Cc: devicetree, srv_heupstream, leilk.liu, linux-kernel, robh+dt, linux-mediatek, linux-i2c, matthias.bgg, linux-arm-kernel [-- Attachment #1.1: Type: text/plain, Size: 314 bytes --] > > Can't you use those to derive your values from that? Which ones are you missing > > if not? > > I have take a little time to develop a new patch which based on your > suggestions, and it tested OK. Thanks for your suggestions, I will > update the patch after I test it fully. Great news, thanks! [-- Attachment #1.2: signature.asc --] [-- Type: application/pgp-signature, Size: 833 bytes --] [-- Attachment #2: Type: text/plain, Size: 176 bytes --] _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 2/2] i2c: mediatek: Add i2c AC timing adjust support 2019-06-11 8:11 [PATCH 0/2] Add support for AC timing adjustment Qii Wang 2019-06-11 8:11 ` [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding Qii Wang @ 2019-06-11 8:11 ` Qii Wang 1 sibling, 0 replies; 6+ messages in thread From: Qii Wang @ 2019-06-11 8:11 UTC (permalink / raw) To: wsa Cc: devicetree, qii.wang, srv_heupstream, leilk.liu, linux-kernel, robh+dt, linux-mediatek, linux-i2c, matthias.bgg, linux-arm-kernel This patch adds some I2C timing registers to meet I2C spec, it configures these registers according to information passed via DT. Signed-off-by: Qii Wang <qii.wang@mediatek.com> --- drivers/i2c/busses/i2c-mt65xx.c | 94 ++++++++++++++++++++++++++++++++++----- 1 file changed, 82 insertions(+), 12 deletions(-) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index 745b0d0..f4bf753 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -134,6 +134,12 @@ enum I2C_REGS_OFFSET { OFFSET_TRANSFER_LEN_AUX, OFFSET_CLOCK_DIV, OFFSET_LTIMING, + OFFSET_SCL_HIGH_LOW_RATIO, + OFFSET_HS_SCL_HIGH_LOW_RATIO, + OFFSET_SCL_MIS_COMP_POINT, + OFFSET_STA_STO_AC_TIMING, + OFFSET_HS_STA_STO_AC_TIMING, + OFFSET_SDA_TIMING, }; static const u16 mt_i2c_regs_v1[] = { @@ -161,6 +167,12 @@ enum I2C_REGS_OFFSET { [OFFSET_DEBUGCTRL] = 0x68, [OFFSET_TRANSFER_LEN_AUX] = 0x6c, [OFFSET_CLOCK_DIV] = 0x70, + [OFFSET_SCL_HIGH_LOW_RATIO] = 0x74, + [OFFSET_HS_SCL_HIGH_LOW_RATIO] = 0x78, + [OFFSET_SCL_MIS_COMP_POINT] = 0x7C, + [OFFSET_STA_STO_AC_TIMING] = 0x80, + [OFFSET_HS_STA_STO_AC_TIMING] = 0x84, + [OFFSET_SDA_TIMING] = 0x88, }; static const u16 mt_i2c_regs_v2[] = { @@ -179,9 +191,11 @@ enum I2C_REGS_OFFSET { [OFFSET_HS] = 0x30, [OFFSET_IO_CONFIG] = 0x34, [OFFSET_FIFO_ADDR_CLR] = 0x38, + [OFFSET_SDA_TIMING] = 0x3c, [OFFSET_TRANSFER_LEN_AUX] = 0x44, [OFFSET_CLOCK_DIV] = 0x48, [OFFSET_SOFTRESET] = 0x50, + [OFFSET_SCL_MIS_COMP_POINT] = 0x90, [OFFSET_DEBUGSTAT] = 0xe0, [OFFSET_DEBUGCTRL] = 0xe8, [OFFSET_FIFO_STAT] = 0xf4, @@ -202,6 +216,17 @@ struct mtk_i2c_compatible { unsigned char ltiming_adjust: 1; }; +struct mtk_i2c_ac_timing { + u16 ext; + u16 inter_clk_div; + u16 scl_hl_ratio; + u16 hs_scl_hl_ratio; + u16 scl_mis_comp; + u16 sta_stop; + u16 hs_sta_stop; + u16 sda_timing; +}; + struct mtk_i2c { struct i2c_adapter adap; /* i2c host adapter */ struct device *dev; @@ -226,6 +251,7 @@ struct mtk_i2c { u16 ltiming_reg; unsigned char auto_restart; bool ignore_restart_irq; + struct mtk_i2c_ac_timing ac_timing; const struct mtk_i2c_compatible *dev_comp; }; @@ -403,13 +429,40 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c) if (i2c->dev_comp->dcm) mtk_i2c_writew(i2c, I2C_DCM_DISABLE, OFFSET_DCM_EN); - if (i2c->dev_comp->timing_adjust) - mtk_i2c_writew(i2c, I2C_DEFAULT_CLK_DIV - 1, OFFSET_CLOCK_DIV); - mtk_i2c_writew(i2c, i2c->timing_reg, OFFSET_TIMING); mtk_i2c_writew(i2c, i2c->high_speed_reg, OFFSET_HS); - if (i2c->dev_comp->ltiming_adjust) - mtk_i2c_writew(i2c, i2c->ltiming_reg, OFFSET_LTIMING); + + if (i2c->dev_comp->timing_adjust) { + mtk_i2c_writew(i2c, i2c->ac_timing.ext, OFFSET_EXT_CONF); + mtk_i2c_writew(i2c, i2c->ac_timing.inter_clk_div - 1, + OFFSET_CLOCK_DIV); + mtk_i2c_writew(i2c, i2c->ac_timing.scl_mis_comp, + OFFSET_SCL_MIS_COMP_POINT); + mtk_i2c_writew(i2c, i2c->ac_timing.sda_timing, + OFFSET_SDA_TIMING); + + if (i2c->dev_comp->ltiming_adjust) { + mtk_i2c_writew(i2c, i2c->timing_reg - + i2c->ac_timing.scl_hl_ratio, + OFFSET_TIMING); + mtk_i2c_writew(i2c, i2c->high_speed_reg - + ((i2c->ac_timing.hs_scl_hl_ratio) << 8), + OFFSET_HS); + mtk_i2c_writew(i2c, i2c->ltiming_reg + + ((i2c->ac_timing.hs_scl_hl_ratio) << 9) + + i2c->ac_timing.scl_hl_ratio, + OFFSET_LTIMING); + } else { + mtk_i2c_writew(i2c, i2c->ac_timing.scl_hl_ratio, + OFFSET_SCL_HIGH_LOW_RATIO); + mtk_i2c_writew(i2c, i2c->ac_timing.hs_scl_hl_ratio, + OFFSET_HS_SCL_HIGH_LOW_RATIO); + mtk_i2c_writew(i2c, i2c->ac_timing.sta_stop, + OFFSET_STA_STO_AC_TIMING); + mtk_i2c_writew(i2c, i2c->ac_timing.hs_sta_stop, + OFFSET_HS_STA_STO_AC_TIMING); + } + } /* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */ if (i2c->have_pmic) @@ -592,12 +645,6 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL); - /* set start condition */ - if (i2c->speed_hz <= I2C_DEFAULT_SPEED) - mtk_i2c_writew(i2c, I2C_ST_START_CON, OFFSET_EXT_CONF); - else - mtk_i2c_writew(i2c, I2C_FS_START_CON, OFFSET_EXT_CONF); - addr_reg = i2c_8bit_addr_from_msg(msgs); mtk_i2c_writew(i2c, addr_reg, OFFSET_SLAVE_ADDR); @@ -889,6 +936,7 @@ static u32 mtk_i2c_functionality(struct i2c_adapter *adap) static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c) { int ret; + u16 ac_timing[8] = {0}; ret = of_property_read_u32(np, "clock-frequency", &i2c->speed_hz); if (ret < 0) @@ -901,6 +949,28 @@ static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c) if (i2c->clk_src_div == 0) return -EINVAL; + if (i2c->dev_comp->timing_adjust) { + ret = of_property_read_u16_array(np, "ac-timing", ac_timing, + ARRAY_SIZE(ac_timing)); + if (ret < 0) { + if (i2c->speed_hz <= I2C_DEFAULT_SPEED) + i2c->ac_timing.ext = I2C_ST_START_CON; + else + i2c->ac_timing.ext = I2C_FS_START_CON; + + i2c->ac_timing.inter_clk_div = I2C_DEFAULT_CLK_DIV; + } else { + i2c->ac_timing.ext = ac_timing[0]; + i2c->ac_timing.inter_clk_div = ac_timing[1]; + i2c->ac_timing.scl_hl_ratio = ac_timing[2]; + i2c->ac_timing.hs_scl_hl_ratio = ac_timing[3]; + i2c->ac_timing.scl_mis_comp = ac_timing[4]; + i2c->ac_timing.sta_stop = ac_timing[5]; + i2c->ac_timing.hs_sta_stop = ac_timing[6]; + i2c->ac_timing.sda_timing = ac_timing[7]; + } + } + i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic"); i2c->use_push_pull = of_property_read_bool(np, "mediatek,use-push-pull"); @@ -951,7 +1021,7 @@ static int mtk_i2c_probe(struct platform_device *pdev) return -EINVAL; if (i2c->dev_comp->timing_adjust) - i2c->clk_src_div *= I2C_DEFAULT_CLK_DIV; + i2c->clk_src_div *= i2c->ac_timing.inter_clk_div; if (i2c->have_pmic && !i2c->dev_comp->pmic_i2c) return -EINVAL; -- 1.7.9.5 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2019-07-17 13:29 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2019-06-11 8:11 [PATCH 0/2] Add support for AC timing adjustment Qii Wang 2019-06-11 8:11 ` [PATCH 1/2] dt-bindings: i2c: Add MediaTek i2c AC timing binding Qii Wang 2019-06-26 13:39 ` Wolfram Sang 2019-07-17 12:55 ` Qii Wang 2019-07-17 13:29 ` Wolfram Sang 2019-06-11 8:11 ` [PATCH 2/2] i2c: mediatek: Add i2c AC timing adjust support Qii Wang
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