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Message-ID: <CACT4zj_iO58CPk_PTfNCot+c2Z1_vcWeVUwH2nPgN-jx43eN2g@mail.gmail.com>
Date: Fri, 21 Aug 2020 19:33:47 +0800
From: Ben Chuang <benchuanggli@...il.com>
To: Ulf Hansson <ulf.hansson@...aro.org>
Cc: Adrian Hunter <adrian.hunter@...el.com>,
"linux-mmc@...r.kernel.org" <linux-mmc@...r.kernel.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
Ben Chuang <ben.chuang@...esyslogic.com.tw>,
Takahiro Akashi <takahiro.akashi@...aro.org>,
greg.tu@...esyslogic.com.tw
Subject: Re: [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select
UHS-II interface
On Tue, Aug 18, 2020 at 7:42 PM Ulf Hansson <ulf.hansson@...aro.org> wrote:
>
> On Fri, 10 Jul 2020 at 13:08, Ben Chuang <benchuanggli@...il.com> wrote:
> >
> > From: Ben Chuang <ben.chuang@...esyslogic.com.tw>
> >
> > The flow of "interface selection and initialization" was a bit modified
> > for UHS-II card. This commit follows the sequence defined in SD
> > specification (Part 1).
> > See section 7.2.3 in "UHS-II Simplified Addendum."
> >
> > Signed-off-by: Ben Chuang <ben.chuang@...esyslogic.com.tw>
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@...aro.org>
> > ---
> > drivers/mmc/core/Makefile | 2 +-
> > drivers/mmc/core/bus.c | 5 +-
> > drivers/mmc/core/core.c | 33 +-
> > drivers/mmc/core/sd.c | 26 ++
> > drivers/mmc/core/uhs2.c | 800 ++++++++++++++++++++++++++++++++++++++
> > drivers/mmc/core/uhs2.h | 20 +
> > 6 files changed, 882 insertions(+), 4 deletions(-)
> > create mode 100644 drivers/mmc/core/uhs2.c
> > create mode 100644 drivers/mmc/core/uhs2.h
> >
> > diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
> > index 95ffe008ebdf..e2a90dc98afc 100644
> > --- a/drivers/mmc/core/Makefile
> > +++ b/drivers/mmc/core/Makefile
> > @@ -8,7 +8,7 @@ mmc_core-y := core.o bus.o host.o \
> > mmc.o mmc_ops.o sd.o sd_ops.o \
> > sdio.o sdio_ops.o sdio_bus.o \
> > sdio_cis.o sdio_io.o sdio_irq.o \
> > - slot-gpio.o regulator.o
> > + slot-gpio.o regulator.o uhs2.o
> > mmc_core-$(CONFIG_OF) += pwrseq.o
> > obj-$(CONFIG_PWRSEQ_SIMPLE) += pwrseq_simple.o
> > obj-$(CONFIG_PWRSEQ_SD8787) += pwrseq_sd8787.o
> > diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
> > index 70207f11a654..66d3e942f3fc 100644
> > --- a/drivers/mmc/core/bus.c
> > +++ b/drivers/mmc/core/bus.c
> > @@ -350,8 +350,9 @@ int mmc_add_card(struct mmc_card *card)
> > } else {
> > pr_info("%s: new %s%s%s%s%s%s card at address %04x\n",
> > mmc_hostname(card->host),
> > - mmc_card_uhs(card) ? "ultra high speed " :
> > - (mmc_card_hs(card) ? "high speed " : ""),
> > + mmc_card_uhs2(card) ? "ultra high speed 2 " :
> > + (mmc_card_uhs(card) ? "ultra high speed 1 " :
>
> Perhaps use "UHS-I" and "UHS-II" instead.
OK, The next version will be changed.
>
> > + (mmc_card_hs(card) ? "high speed " : "")),
> > mmc_card_hs400(card) ? "HS400 " :
> > (mmc_card_hs200(card) ? "HS200 " : ""),
> > mmc_card_hs400es(card) ? "Enhanced strobe " : "",
> > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> > index c6540d56646b..e2534f3446ce 100644
> > --- a/drivers/mmc/core/core.c
> > +++ b/drivers/mmc/core/core.c
> > @@ -31,6 +31,7 @@
> > #include <linux/mmc/mmc.h>
> > #include <linux/mmc/sd.h>
> > #include <linux/mmc/slot-gpio.h>
> > +#include <linux/mmc/uhs2.h>
> >
> > #define CREATE_TRACE_POINTS
> > #include <trace/events/mmc.h>
> > @@ -41,6 +42,7 @@
> > #include "host.h"
> > #include "sdio_bus.h"
> > #include "pwrseq.h"
> > +#include "uhs2.h"
> >
> > #include "mmc_ops.h"
> > #include "sd_ops.h"
> > @@ -51,6 +53,7 @@
> > #define SD_DISCARD_TIMEOUT_MS (250)
> >
> > static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
> > +static const unsigned int uhs2_freqs[] = { 52000000, 26000000 };
> >
> > /*
> > * Enabling software CRCs on the data blocks can be a significant (30%)
> > @@ -2165,9 +2168,10 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
> > if (!mmc_attach_sdio(host))
> > return 0;
> >
> > - if (!(host->caps2 & MMC_CAP2_NO_SD))
> > + if (!(host->caps2 & MMC_CAP2_NO_SD)) {
> > if (!mmc_attach_sd(host))
> > return 0;
> > + }
> >
> > if (!(host->caps2 & MMC_CAP2_NO_MMC))
> > if (!mmc_attach_mmc(host))
> > @@ -2300,6 +2304,33 @@ void mmc_rescan(struct work_struct *work)
> > goto out;
> > }
> >
> > + if (host->caps & MMC_CAP_UHS2) {
> > + /*
> > + * Start to try UHS-II initialization from 52MHz to 26MHz
> > + * (RCLK range) per spec.
> > + */
> > + for (i = 0; i < ARRAY_SIZE(uhs2_freqs); i++) {
> > + unsigned int freq = uhs2_freqs[i];
> > + int err;
> > +
> > + err = mmc_uhs2_rescan_try_freq(host,
> > + max(freq, host->f_min));
> > + if (!err) {
> > + mmc_release_host(host);
> > + goto out;
> > + }
> > +
> > + if (err == UHS2_PHY_INIT_ERR)
> > + /* UHS2 IF detect or Lane Sync error.
> > + * Try legacy interface.
> > + */
> > + break;
> > +
> > + if (freq <= host->f_min)
> > + break;
> > + }
>
> Assuming we change the initialization order, trying to initialize the
> legacy SD interface first to figure out if UHS-II is supported, then I
> think we should be able to move the entire code above into a the
> UHS-II specific code/path.
If the host tries to use the SD interface first,
some failure status needs to be considered.
For example, first run in SD mode, try UHS-II interface failure,
and then return to SD flow again.
I don't know a good way to go back to SD flow again.
>
> > + }
> > +
> > for (i = 0; i < ARRAY_SIZE(freqs); i++) {
> > unsigned int freq = freqs[i];
> > if (freq > host->f_max) {
> > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> > index 5a2210c25aa7..c5b071bd98b3 100644
> > --- a/drivers/mmc/core/sd.c
> > +++ b/drivers/mmc/core/sd.c
> > @@ -901,6 +901,20 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
> > err = mmc_read_switch(card);
> > if (err)
> > return err;
> > + if (host->flags & MMC_UHS2_INITIALIZED) {
>
> Rather than using host->flags, to tweak the behavior of
> mmc_sd_setup_card() to support UHS-II, I would prefer to give
> mmc_sd_setup_card() a new in-parameter that it can look at instead.
Do you mean that adding a new in-parameter to mmc_sd_setup_card() likes this
mmc_sd_setup_card(struct mmc_host *, struct mmc_card *, boot reinit,
boot uhsii); ?
>
> > + u8 status[64];
> > + /*
> > + * send CMD6 to set Maximum Power Consumption
> > + * to get better performance
> > + */
> > + err = mmc_sd_switch(card, 0, 3,
> > + SD_SET_CURRENT_LIMIT_1000, status);
> > + if (!err) {
> > + err = mmc_sd_switch(card, 1, 3,
> > + SD_SET_CURRENT_LIMIT_1000,
> > + status);
> > + }
> > + }
> > }
> >
> > /*
> > @@ -1043,6 +1057,11 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
> > if (err)
> > goto free_card;
> >
> > + /* For UHS2, skip the UHS-I initialization. */
> > + if ((host->flags & MMC_UHS2_SUPPORT) &&
> > + (host->flags & MMC_UHS2_INITIALIZED))
> > + goto done;
>
> mmc_sd_init_card() is also called at system resume, to re-initialize the card.
>
> Re-initialization is going to be needed for UHS-II cards as well,
> since we should ideally avoid wasting energy in system suspend state
> for these cards as well.
>
> Perhaps you haven't looked at that part yet? Or I may be missing something here?
Yes, I didn't look at that power management. It should be considered.
>
> > +
> > /*
> > * If the card has not been power cycled, it may still be using 1.8V
> > * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
> > @@ -1334,6 +1353,13 @@ int mmc_attach_sd(struct mmc_host *host)
> >
> > rocr = mmc_select_voltage(host, ocr);
> >
> > + /*
> > + * Some cards have zero value of rocr in UHS-II mode. Assign host's ocr
> > + * value to rocr.
> > + */
> > + if ((host->flags & MMC_UHS2_INITIALIZED) && !rocr)
> > + rocr = host->ocr_avail;
>
> As stated already earlier above, we should probably be able to move
> any UHS-II specific bits to the UHS-II code/path.
>
> > +
> > /*
> > * Can we support the voltage(s) of the card(s)?
> > */
> > diff --git a/drivers/mmc/core/uhs2.c b/drivers/mmc/core/uhs2.c
> > new file mode 100644
> > index 000000000000..a3b20ac6f315
> > --- /dev/null
> > +++ b/drivers/mmc/core/uhs2.c
> > @@ -0,0 +1,800 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +/*
> > + * linux/drivers/mmc/core/uhs2.c - UHS-II driver
> > + *
> > + * Copyright (C) 2014 Intel Corp, All Rights Reserved.
> > + * Copyright (C) 2020 Genesys Logic, Inc.
> > + * Authors: Ben Chuang <ben.chuang@...esyslogic.com.tw>
> > + * Copyright (C) 2020 Linaro Limited
> > + * Author: AKASHI Takahiro <takahiro.akashi@...aro.org>
> > + */
> > +
> > +#include <asm/byteorder.h>
> > +#include <linux/err.h>
> > +#include <linux/slab.h>
> > +
> > +#include <linux/mmc/host.h>
> > +#include <linux/mmc/card.h>
> > +#include <linux/mmc/mmc.h>
> > +#include <linux/mmc/core.h>
> > +#include <linux/mmc/sdio.h>
> > +#include <linux/mmc/slot-gpio.h>
> > +#include <linux/mmc/uhs2.h>
> > +
> > +#include "uhs2.h"
> > +#include "mmc_ops.h"
> > +#include "sd_ops.h"
> > +#include "core.h"
> > +
> > +#define DBG(f, x...) \
> > + pr_warn("[%s()]: " f, __func__, ## x)
> > +
> > +/**
> > + * uhs2_cmd_assemble - assemble and build up uhs2 command
> > + * @cmd: MMC command
> > + * @uhs2_cmd: UHS2 command
> > + * @header: Value of packet header
> > + * @arg: Argument of packet
> > + * @payload: Payload of packet
> > + * @plen: Payload length
> > + * @resp: Buffer for response
> > + * @resp_len: Response buffer length
> > + *
> > + * resp is inputted outside which should be a variable created by caller
> > + * so caller should handle it. For SD command, there is no uhs2_resp and
> > + * response should be stored in resp of mmc_command.
> > + */
> > +static void uhs2_cmd_assemble(struct mmc_command *cmd,
> > + struct uhs2_command *uhs2_cmd,
> > + u16 header, u16 arg,
> > + u32 *payload, u8 plen, u8 *resp, u8 resp_len)
> > +{
> > + uhs2_cmd->header = header;
> > + uhs2_cmd->arg = arg;
> > + uhs2_cmd->payload = payload;
> > + uhs2_cmd->payload_len = plen * sizeof(u32);
> > + uhs2_cmd->packet_len = uhs2_cmd->payload_len + 4;
> > +
> > + cmd->uhs2_cmd = uhs2_cmd;
> > + cmd->uhs2_resp = resp;
> > + cmd->uhs2_resp_len = resp_len;
> > +
> > + pr_debug("%s: uhs2_cmd: header=0x%x arg=0x%x\n",
> > + __func__, uhs2_cmd->header, uhs2_cmd->arg);
> > + pr_debug("%s: payload_len=%d packet_len=%d resp_len=%d\n",
> > + __func__, uhs2_cmd->payload_len, uhs2_cmd->packet_len,
> > + cmd->uhs2_resp_len);
>
> I noticed that there is lots of debug code around. I understand that
> it's useful during development, but I think we should be able to
> remove some of it. Can you please have a look and clean up that?
OK, debug codes will be cleared.
>
> > +}
> > +
> > +static int uhs2_dev_init(struct mmc_host *host)
> > +{
> > + struct mmc_command cmd = {0};
> > + struct uhs2_command uhs2_cmd = {};
> > + u32 cnt;
> > + u32 dap, gap, gap1;
> > + u16 header = 0, arg = 0;
> > + u32 payload[1];
> > + u8 plen = 1;
> > + u8 gd = 0, cf = 1;
> > + u8 resp[6] = {0};
> > + u8 resp_len = 6;
> > + int err;
> > +
> > + dap = host->uhs2_caps.dap;
> > + gap = host->uhs2_caps.gap;
> > +
> > + header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> > + arg = ((UHS2_DEV_CMD_DEVICE_INIT & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_WRITE |
> > + UHS2_NATIVE_CMD_PLEN_4B |
> > + (UHS2_DEV_CMD_DEVICE_INIT >> 8);
> > +
> > + /* need this for some cards */
> > + cmd.busy_timeout = 1000;
>
> Is this according to spec? Please add defines for timeout values.
In UHS-II Addenum, table 6-25: device timing parameters in CM_TRAN,
Please see `initialization' row in table 6-25.
I will define it like "#define UHSII_DEVINIT_CMD_TIMEOUT 1000".
>
> > +
> > + for (cnt = 0; cnt < 30; cnt++) {
> > + payload[0] = ((dap & 0xF) << 12) |
> > + (cf << 11) |
> > + ((gd & 0xF) << 4) |
> > + (gap & 0xF);
> > +
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> > + payload, plen, resp, resp_len);
> > +
> > + DBG("Begin DEVICE_INIT, header=0x%x, arg=0x%x, payload=0x%x.\n",
> > + header, arg, payload[0]);
> > +
> > + DBG("Sending DEVICE_INIT. Count = %d\n", cnt);
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
>
> Debug code, please clean this up...
OK.
>
> > +
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
>
> Debug code, please clean this up. I am stopping from commenting on
> that, as stated, please have a look at all the code to clean this up.
OK, I will remove debug codes as much as possible.
>
> > + int i;
> > +
> > + pr_warn("%s: DEVICE_INIT response is: ",
> > + mmc_hostname(host));
> > + for (i = 0; i < resp_len; i++)
> > + pr_warn("0x%x ", resp[i]);
> > + pr_warn("\n");
> > + }
> > +
> > + if (resp[3] != (UHS2_DEV_CMD_DEVICE_INIT & 0xFF)) {
> > + pr_err("%s: DEVICE_INIT response is wrong!\n",
> > + mmc_hostname(host));
> > + return -EIO;
> > + }
> > +
> > + if (resp[5] & 0x8) {
> > + DBG("CF is set, device is initialized!\n");
> > + host->group_desc = gd;
> > + break;
> > + }
> > + gap1 = resp[4] & 0x0F;
> > + if (gap == gap1)
> > + gd++;
> > + }
> > + if (cnt == 30) {
> > + pr_err("%s: DEVICE_INIT fail, already 30 times!\n",
> > + mmc_hostname(host));
> > + return -EIO;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int uhs2_enum(struct mmc_host *host)
> > +{
> > + struct mmc_command cmd = {0};
> > + struct uhs2_command uhs2_cmd = {};
> > + u16 header = 0, arg = 0;
> > + u32 payload[1];
> > + u8 plen = 1;
> > + u8 id_f = 0xF, id_l = 0x0;
> > + u8 resp[8] = {0};
> > + u8 resp_len = 8;
> > + int err;
> > +
> > + header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> > + arg = ((UHS2_DEV_CMD_ENUMERATE & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_WRITE |
> > + UHS2_NATIVE_CMD_PLEN_4B |
> > + (UHS2_DEV_CMD_ENUMERATE >> 8);
> > +
> > + payload[0] = (id_f << 4) | id_l;
> > +
> > + DBG("Begin ENUMERATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
> > + header, arg, payload[0]);
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> > + resp, resp_len);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > + int i;
> > +
> > + pr_warn("%s: ENUMERATE response is: ", mmc_hostname(host));
> > + for (i = 0; i < resp_len; i++)
> > + pr_warn("0x%x ", resp[i]);
> > + pr_warn("\n");
> > + }
> > +
> > + if (resp[3] != (UHS2_DEV_CMD_ENUMERATE & 0xFF)) {
> > + pr_err("%s: ENUMERATE response is wrong!\n",
> > + mmc_hostname(host));
> > + return -EIO;
> > + }
> > +
> > + id_f = (resp[4] >> 4) & 0xF;
> > + id_l = resp[4] & 0xF;
> > + DBG("id_f = %d, id_l = %d.\n", id_f, id_l);
> > + DBG("Enumerate Cmd Completed. No. of Devices connected = %d\n",
> > + id_l - id_f + 1);
> > + host->uhs2_dev_prop.node_id = id_f;
> > +
> > + return 0;
> > +}
> > +
> > +static int uhs2_config_read(struct mmc_host *host)
> > +{
> > + struct mmc_command cmd = {0};
> > + struct uhs2_command uhs2_cmd = {};
> > + u16 header = 0, arg = 0;
> > + u32 cap;
> > + int err;
> > +
> > + DBG("INQUIRY_CFG: read Generic Caps.\n");
> > + header = UHS2_NATIVE_PACKET |
> > + UHS2_PACKET_TYPE_CCMD |
> > + host->uhs2_dev_prop.node_id;
> > + arg = ((UHS2_DEV_CONFIG_GEN_CAPS & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_READ |
> > + UHS2_NATIVE_CMD_PLEN_4B |
> > + (UHS2_DEV_CONFIG_GEN_CAPS >> 8);
> > +
> > + DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> > + header, arg);
> > + /* There is no payload because per spec, there should be
> > + * no payload field for read CCMD.
> > + * Plen is set in arg. Per spec, plen for read CCMD
> > + * represents the len of read data which is assigned in payload
> > + * of following RES (p136).
> > + */
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > + int i;
> > +
> > + pr_warn("%s: INQUIRY_CFG generic response is: ",
> > + mmc_hostname(host));
> > + for (i = 0; i < 2; i++)
> > + pr_warn("0x%x ", cmd.resp[i]);
> > + pr_warn("\n");
> > + }
> > +
> > + cap = cmd.resp[0];
> > + DBG("Device Generic Caps (0-31) is: 0x%x.\n", cap);
> > + host->uhs2_dev_prop.n_lanes = (cap >> UHS2_DEV_CONFIG_N_LANES_POS) &
> > + UHS2_DEV_CONFIG_N_LANES_MASK;
> > + host->uhs2_dev_prop.dadr_len = (cap >> UHS2_DEV_CONFIG_DADR_POS) &
> > + UHS2_DEV_CONFIG_DADR_MASK;
> > + host->uhs2_dev_prop.app_type = (cap >> UHS2_DEV_CONFIG_APP_POS) &
> > + UHS2_DEV_CONFIG_APP_MASK;
> > +
> > + DBG("INQUIRY_CFG: read PHY Caps.\n");
> > + arg = ((UHS2_DEV_CONFIG_PHY_CAPS & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_READ |
> > + UHS2_NATIVE_CMD_PLEN_8B |
> > + (UHS2_DEV_CONFIG_PHY_CAPS >> 8);
> > +
> > + DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> > + header, arg);
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > + int i;
> > +
> > + pr_warn("%s: INQUIRY_CFG PHY response is: ",
> > + mmc_hostname(host));
> > + for (i = 0; i < 2; i++)
> > + pr_warn("0x%x ", cmd.resp[i]);
> > + pr_warn("\n");
> > + }
> > +
> > + cap = cmd.resp[0];
> > + DBG("Device PHY Caps (0-31) is: 0x%x.\n", cap);
> > + host->uhs2_dev_prop.phy_minor_rev = cap &
> > + UHS2_DEV_CONFIG_PHY_MINOR_MASK;
> > + host->uhs2_dev_prop.phy_major_rev = (cap >>
> > + UHS2_DEV_CONFIG_PHY_MAJOR_POS) &
> > + UHS2_DEV_CONFIG_PHY_MAJOR_MASK;
> > + host->uhs2_dev_prop.can_hibernate = (cap >>
> > + UHS2_DEV_CONFIG_CAN_HIBER_POS) &
> > + UHS2_DEV_CONFIG_CAN_HIBER_MASK;
> > +
> > + cap = cmd.resp[1];
> > + DBG("Device PHY Caps (32-63) is: 0x%x.\n", cap);
> > + host->uhs2_dev_prop.n_lss_sync = cap & UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> > + host->uhs2_dev_prop.n_lss_dir = (cap >>
> > + UHS2_DEV_CONFIG_N_LSS_DIR_POS) &
> > + UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > + if (host->uhs2_dev_prop.n_lss_sync == 0)
> > + host->uhs2_dev_prop.n_lss_sync = 16 << 2;
> > + else
> > + host->uhs2_dev_prop.n_lss_sync <<= 2;
> > +
> > + if (host->uhs2_dev_prop.n_lss_dir == 0)
> > + host->uhs2_dev_prop.n_lss_dir = 16 << 3;
> > + else
> > + host->uhs2_dev_prop.n_lss_dir <<= 3;
> > +
> > + DBG("INQUIRY_CFG: read LINK-TRAN Caps.\n");
> > + arg = ((UHS2_DEV_CONFIG_LINK_TRAN_CAPS & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_READ |
> > + UHS2_NATIVE_CMD_PLEN_8B |
> > + (UHS2_DEV_CONFIG_LINK_TRAN_CAPS >> 8);
> > +
> > + DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> > + header, arg);
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > + int i;
> > +
> > + pr_warn("%s: INQUIRY_CFG Link-Tran response is: ",
> > + mmc_hostname(host));
> > + for (i = 0; i < 2; i++)
> > + pr_warn("0x%x ", cmd.resp[i]);
> > + pr_warn("\n");
> > + }
> > +
> > + cap = cmd.resp[0];
> > + DBG("Device LINK-TRAN Caps (0-31) is: 0x%x.\n", cap);
> > + host->uhs2_dev_prop.link_minor_rev = cap &
> > + UHS2_DEV_CONFIG_LT_MINOR_MASK;
> > + host->uhs2_dev_prop.link_major_rev = (cap >>
> > + UHS2_DEV_CONFIG_LT_MAJOR_POS) &
> > + UHS2_DEV_CONFIG_LT_MAJOR_MASK;
> > + host->uhs2_dev_prop.n_fcu = (cap >> UHS2_DEV_CONFIG_N_FCU_POS) &
> > + UHS2_DEV_CONFIG_N_FCU_MASK;
> > + host->uhs2_dev_prop.dev_type = (cap >> UHS2_DEV_CONFIG_DEV_TYPE_POS) &
> > + UHS2_DEV_CONFIG_DEV_TYPE_MASK;
> > + host->uhs2_dev_prop.maxblk_len = (cap >>
> > + UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) &
> > + UHS2_DEV_CONFIG_MAX_BLK_LEN_MASK;
> > +
> > + cap = cmd.resp[1];
> > + DBG("Device LINK-TRAN Caps (32-63) is: 0x%x.\n", cap);
> > + host->uhs2_dev_prop.n_data_gap = cap & UHS2_DEV_CONFIG_N_DATA_GAP_MASK;
> > + if (host->uhs2_dev_prop.n_fcu == 0)
> > + host->uhs2_dev_prop.n_fcu = 256;
> > +
> > + return 0;
> > +}
> > +
> > +static int uhs2_config_write(struct mmc_host *host)
> > +{
> > + struct mmc_command cmd = {0};
> > + struct uhs2_command uhs2_cmd = {};
> > + u16 header = 0, arg = 0;
> > + u32 nTry;
> > + u32 payload[2];
> > + u8 nMinDataGap;
> > + u8 plen;
> > + int err;
> > + u8 resp[5] = {0};
> > + u8 resp_len = 5;
> > + /*
> > + * must long enough for RECV_SW_DIR == 2;
> > + * need lss_dir at least 4 for GL9755 device
> > + * max compitable g_lss_dir = 0
> > + */
> > + u32 g_lss_dir = 0;
> > +
> > + DBG("SET_COMMON_CFG: write Generic Settings.\n");
> > + header = UHS2_NATIVE_PACKET |
> > + UHS2_PACKET_TYPE_CCMD | host->uhs2_dev_prop.node_id;
> > + arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_WRITE |
> > + UHS2_NATIVE_CMD_PLEN_8B |
> > + (UHS2_DEV_CONFIG_GEN_SET >> 8);
> > +
> > + if (host->uhs2_dev_prop.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD &&
> > + host->uhs2_caps.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD) {
> > + /* Support HD */
> > + DBG("Both Host and device support 2L-HD.\n");
> > + host->flags |= MMC_UHS2_2L_HD;
> > + host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > + host->uhs2_dev_prop.n_lanes_set =
> > + UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > + nMinDataGap = 1;
> > + } else {
> > + /* Only support 2L-FD so far */
> > + host->flags &= ~MMC_UHS2_2L_HD;
> > + host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > + host->uhs2_dev_prop.n_lanes_set =
> > + UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > + nMinDataGap = 3;
> > + }
> > +
> > + plen = 2;
> > + payload[0] = host->uhs2_dev_prop.n_lanes_set <<
> > + UHS2_DEV_CONFIG_N_LANES_POS;
> > + payload[1] = 0;
> > + payload[0] = cpu_to_be32(payload[0]);
> > + payload[1] = cpu_to_be32(payload[1]);
> > +
> > + DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x\n", header, arg);
> > + DBG("UHS2 write Generic Settings %08x %08x\n",
> > + payload[0], payload[1]);
> > + DBG("flags=%08x dev_prop.n_lanes_set=%x host_caps.n_lanes_set=%x\n",
> > + host->flags,
> > + host->uhs2_dev_prop.n_lanes_set,
> > + host->uhs2_caps.n_lanes_set);
> > +
> > + /*
> > + * There is no payload because per spec, there should be
> > + * no payload field for read CCMD.
> > + * Plen is set in arg. Per spec, plen for read CCMD
> > + * represents the len of read data which is assigned in payload
> > + * of following RES (p136).
> > + */
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + DBG("SET_COMMON_CFG: PHY Settings.\n");
> > + arg = ((UHS2_DEV_CONFIG_PHY_SET & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_WRITE |
> > + UHS2_NATIVE_CMD_PLEN_8B |
> > + (UHS2_DEV_CONFIG_PHY_SET >> 8);
> > +
> > + for (nTry = 0; nTry < 2; nTry++) {
> > + plen = 2;
> > +
> > + if (host->uhs2_caps.speed_range ==
> > + UHS2_DEV_CONFIG_PHY_SET_SPEED_B) {
> > + host->flags |= MMC_UHS2_SPEED_B;
> > + host->uhs2_dev_prop.speed_range_set =
> > + UHS2_DEV_CONFIG_PHY_SET_SPEED_B;
> > + DBG("set dev_prop.speed_range_set to SPEED_B\n");
> > + } else {
> > + host->uhs2_dev_prop.speed_range_set =
> > + UHS2_DEV_CONFIG_PHY_SET_SPEED_A;
> > + host->flags &= ~MMC_UHS2_SPEED_B;
> > + DBG("set dev_prop.speed_range_set to SPEED_A\n");
> > + }
> > +
> > + payload[0] = host->uhs2_dev_prop.speed_range_set <<
> > + UHS2_DEV_CONFIG_PHY_SET_SPEED_POS;
> > +
> > + host->uhs2_dev_prop.n_lss_sync_set =
> > + (min(host->uhs2_dev_prop.n_lss_sync,
> > + host->uhs2_caps.n_lss_sync) >> 2) &
> > + UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> > + host->uhs2_caps.n_lss_sync_set =
> > + host->uhs2_dev_prop.n_lss_sync_set;
> > +
> > + if (nTry) {
> > + host->uhs2_dev_prop.n_lss_dir_set =
> > + (max(host->uhs2_dev_prop.n_lss_dir,
> > + host->uhs2_caps.n_lss_dir) >> 3) &
> > + UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > + host->uhs2_caps.n_lss_dir_set =
> > + host->uhs2_dev_prop.n_lss_dir_set;
> > + payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
> > + UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
> > + host->uhs2_dev_prop.n_lss_sync_set;
> > + } else {
> > + host->uhs2_caps.n_lss_dir_set =
> > + (host->uhs2_dev_prop.n_lss_dir >> 3) &
> > + UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > + host->uhs2_dev_prop.n_lss_dir_set =
> > + ((host->uhs2_caps.n_lss_dir >> 3) + 1) &
> > + UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > + }
> > +
> > + if (!g_lss_dir) {
> > + host->uhs2_dev_prop.n_lss_dir_set = 0;
> > + } else {
> > + host->uhs2_dev_prop.n_lss_dir_set =
> > + max((u8)g_lss_dir,
> > + host->uhs2_dev_prop.n_lss_dir_set);
> > + }
> > +
> > + payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
> > + UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
> > + host->uhs2_dev_prop.n_lss_sync_set;
> > + payload[0] = cpu_to_be32(payload[0]);
> > + payload[1] = cpu_to_be32(payload[1]);
> > +
> > + DBG("UHS2 SET PHY Settings %08x %08x\n",
> > + payload[0], payload[1]);
> > + DBG("host->flags=%08x dev_prop.speed_range_set=%x\n",
> > + host->flags,
> > + host->uhs2_dev_prop.speed_range_set);
> > + DBG("dev_prop.n_lss_sync_set=%x host_caps.n_lss_sync_set=%x\n",
> > + host->uhs2_dev_prop.n_lss_sync_set,
> > + host->uhs2_caps.n_lss_sync_set);
> > + DBG("dev_prop.n_lss_dir_set=%x host_caps.n_lss_dir_set=%x\n",
> > + host->uhs2_dev_prop.n_lss_dir_set,
> > + host->uhs2_caps.n_lss_dir_set);
> > +
> > + DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n",
> > + header, arg);
> > + DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n",
> > + payload[0], payload[1]);
> > +
> > + resp_len = 4;
> > + memset(resp, 0, sizeof(resp));
> > +
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> > + payload, plen, resp, resp_len);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + if (!(resp[2] & 0x80))
> > + break;
> > +
> > + DBG("%s: %s: UHS2 SET PHY Settings fail, res= 0x%x!\n",
> > + mmc_hostname(host), __func__, resp[2]);
> > + }
> > +
> > + DBG("SET_COMMON_CFG: LINK-TRAN Settings.\n");
> > + arg = ((UHS2_DEV_CONFIG_LINK_TRAN_SET & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_WRITE |
> > + UHS2_NATIVE_CMD_PLEN_8B |
> > + (UHS2_DEV_CONFIG_LINK_TRAN_SET >> 8);
> > +
> > + plen = 2;
> > +
> > + if (host->uhs2_dev_prop.app_type == UHS2_DEV_CONFIG_APP_SD_MEM)
> > + host->uhs2_dev_prop.maxblk_len_set =
> > + UHS2_DEV_CONFIG_LT_SET_MAX_BLK_LEN;
> > + else
> > + host->uhs2_dev_prop.maxblk_len_set =
> > + min(host->uhs2_dev_prop.maxblk_len,
> > + host->uhs2_caps.maxblk_len);
> > + host->uhs2_caps.maxblk_len_set = host->uhs2_dev_prop.maxblk_len_set;
> > +
> > + host->uhs2_dev_prop.n_fcu_set =
> > + min(host->uhs2_dev_prop.n_fcu,
> > + host->uhs2_caps.n_fcu);
> > + host->uhs2_caps.n_fcu_set = host->uhs2_dev_prop.n_fcu_set;
> > +
> > + host->uhs2_dev_prop.n_data_gap_set =
> > + max(nMinDataGap, host->uhs2_dev_prop.n_data_gap);
> > +
> > + host->uhs2_caps.n_data_gap_set = host->uhs2_dev_prop.n_data_gap_set;
> > +
> > + host->uhs2_caps.max_retry_set = 3;
> > + host->uhs2_dev_prop.max_retry_set = host->uhs2_caps.max_retry_set;
> > +
> > + payload[0] = (host->uhs2_dev_prop.maxblk_len_set <<
> > + UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) |
> > + (host->uhs2_dev_prop.max_retry_set <<
> > + UHS2_DEV_CONFIG_LT_SET_MAX_RETRY_POS) |
> > + (host->uhs2_dev_prop.n_fcu_set <<
> > + UHS2_DEV_CONFIG_N_FCU_POS);
> > + payload[1] = host->uhs2_dev_prop.n_data_gap_set;
> > + payload[0] = cpu_to_be32(payload[0]);
> > + payload[1] = cpu_to_be32(payload[1]);
> > +
> > + DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n", header, arg);
> > + DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n", payload[0], payload[1]);
> > +
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + DBG("SET_COMMON_CFG: Set Config Completion.\n");
> > + arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_WRITE |
> > + UHS2_NATIVE_CMD_PLEN_8B |
> > + (UHS2_DEV_CONFIG_GEN_SET >> 8);
> > +
> > + plen = 2;
> > + payload[0] = 0;
> > + payload[1] = UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE;
> > + payload[0] = cpu_to_be32(payload[0]);
> > + payload[1] = cpu_to_be32(payload[1]);
> > +
> > + DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x, payload[0] = 0x%x.\n",
> > + header, arg, payload[0]);
> > + resp_len = 5;
> > + memset(resp, 0, sizeof(resp));
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> > + resp, resp_len);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + /* Set host Config Setting registers */
> > + if (host->ops->uhs2_set_reg(host, SET_CONFIG)) {
> > + pr_err("%s: %s: UHS2 SET_CONFIG fail!\n",
> > + mmc_hostname(host), __func__);
> > + return -EIO;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int uhs2_go_dormant(struct mmc_host *host, bool hibernate)
> > +{
> > + struct mmc_command cmd = {0};
> > + struct uhs2_command uhs2_cmd = {};
> > + u16 header = 0, arg = 0;
> > + u32 payload[1];
> > + u8 plen = 1;
> > + int err;
> > +
> > + /* Disable Normal INT */
> > + if (host->ops->uhs2_set_reg(host, DISABLE_INT)) {
> > + pr_err("%s: %s: UHS2 DISABLE_INT fail!\n",
> > + mmc_hostname(host), __func__);
> > + return -EIO;
> > + }
> > +
> > + header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD |
> > + host->uhs2_dev_prop.node_id;
> > +
> > + arg = ((UHS2_DEV_CMD_GO_DORMANT_STATE & 0xFF) << 8) |
> > + UHS2_NATIVE_CMD_WRITE |
> > + UHS2_NATIVE_CMD_PLEN_4B |
> > + (UHS2_DEV_CMD_GO_DORMANT_STATE >> 8);
> > +
> > + if (hibernate)
> > + payload[0] = UHS2_DEV_CMD_DORMANT_HIBER;
> > +
> > + DBG("Begin GO_DORMANT_STATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
> > + header, arg, payload[0]);
> > + uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> > +
> > + err = mmc_wait_for_cmd(host, &cmd, 0);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + /* Check Dormant State in Present */
> > + if (host->ops->uhs2_set_reg(host, CHECK_DORMANT)) {
> > + pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail!\n",
> > + mmc_hostname(host), __func__);
> > + return -EIO;
> > + }
> > +
> > + host->ops->uhs2_disable_clk(host);
> > +
> > + return 0;
> > +}
> > +
> > +static int uhs2_change_speed(struct mmc_host *host)
> > +{
> > + int err;
> > +
> > + /* Change Speed Range */
> > + if (host->ops->uhs2_set_reg(host, SET_SPEED_B)) {
> > + pr_err("%s: %s: UHS2 SET_SPEED fail!\n",
> > + mmc_hostname(host), __func__);
> > + return -EIO;
> > + }
> > +
> > + err = uhs2_go_dormant(host, false);
> > + if (err) {
> > + pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail, err= 0x%x!\n",
> > + mmc_hostname(host), __func__, err);
> > + return -EIO;
> > + }
> > +
> > + /* restore sd clock */
> > + mdelay(5);
> > + host->ops->uhs2_enable_clk(host);
> > +
> > + /* Enable Normal INT */
> > + if (host->ops->uhs2_set_reg(host, ENABLE_INT)) {
> > + pr_err("%s: %s: UHS2 ENABLE_INT fail!\n",
> > + mmc_hostname(host), __func__);
> > + return -EIO;
> > + }
> > +
> > + if (host->ops->uhs2_detect_init(host)) {
> > + pr_err("%s: %s: uhs2_detect_init() fail!\n",
> > + mmc_hostname(host), __func__);
> > + return -EIO;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +/**
> > + * mmc_uhs2_rescan_try_freq - select UHS2 interface
> > + * @host: MMC host
> > + * @freq: Bus speed
> > + *
> > + * Try to select UHS2 interface and initialize the bus for a given
> > + * frequency, @freq.
> > + *
> > + * Return: 0 on success, non-zero error on failure
> > + */
> > +int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq)
> > +{
> > + int err = -EIO;
> > +
> > + host->flags |= MMC_UHS2_SUPPORT;
> > + host->f_init = freq;
> > +
> > + pr_debug("%s: %s: trying to init card at %u Hz\n",
> > + mmc_hostname(host), __func__, host->f_init);
> > +
> > + mmc_power_up(host, 0);
> > + if (host->ops->uhs2_detect_init(host)) {
> > + pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));
> > + err = UHS2_PHY_INIT_ERR;
> > + goto init_fail;
> > + }
> > +
> > + if (uhs2_dev_init(host)) {
> > + pr_err("%s: UHS2 DEVICE_INIT fail!\n", mmc_hostname(host));
> > + goto init_fail;
> > + }
> > +
> > + if (uhs2_enum(host)) {
> > + pr_err("%s: UHS2 ENUMERATE fail!\n", mmc_hostname(host));
> > + goto init_fail;
> > + }
> > +
> > + if (uhs2_config_read(host)) {
> > + pr_err("%s: UHS2 INQUIRY_CONFIG fail!\n", mmc_hostname(host));
> > + goto init_fail;
> > + }
> > +
> > + if (uhs2_config_write(host)) {
> > + pr_err("%s: UHS2 SET_COMMON_CONFIG fail!\n",
> > + mmc_hostname(host));
> > + goto init_fail;
> > + }
> > +
> > + mmc_delay(10);
> > +
> > + /* Change to Speed Range B if it is supported */
> > + if (host->flags & MMC_UHS2_SPEED_B)
> > + if (uhs2_change_speed(host)) {
> > + pr_err("%s: UHS2 uhs2_change_speed() fail!\n",
> > + mmc_hostname(host));
> > + goto init_fail;
> > + }
> > +
> > + host->flags |= MMC_UHS2_INITIALIZED;
> > +
> > + mmc_send_if_cond(host, host->ocr_avail);
> > +
> > + /* On market, only can some SD cards support UHS-II so only call SD
> > + * attach process here.
> > + */
>
> Not sure I understand this comment, can you please elaborate?
Please ignore the comment. I will delete it.
>
> > + if (!(host->caps2 & MMC_CAP2_NO_SD)) {
> > + err = mmc_attach_sd(host);
>
> While looking at this, perhaps we should simply add a new mmc_bus_ops
> for UHS-II cards, rather than re-using the mmc_sd_ops. Have you
> considered that?
Thanks for this suggestion. I'll mull it over.
>
> There are a couple of reasons why I think it could make sense.
>
> *) The UHS-II code becomes more standalone, which seems like a good
> idea since there really is lots of difference compared with the legacy
> SD interface.
> **) It would enable more flexibility and thus allow for easier UHS-II
> optimizations. For example, it would make power management potentially
> easier to support, as UHS-II re-initialization doesn't seem to have
> much in common with legacy SD.
>
I haven't studied the power management subsystem part at present.
If creating a new mmc_bus_ops can help simplify the power
management,it can be considered.
So there's currently no plan to modify the architecture.
> For those parts that are still common, sharing legacy SD functions via
> common header files can be done, along the lines of what we do between
> MMC and SD already.
Thanks for your comments . I still have a lot to learn and study.
>
> > + if (!err)
> > + return 0;
> > + } else {
> > + err = -EIO;
> > + }
> > +
> > +init_fail:
> > + mmc_power_off(host);
> > + if (host->flags & MMC_UHS2_INITIALIZED)
> > + host->flags &= ~MMC_UHS2_INITIALIZED;
> > + host->flags &= ~MMC_UHS2_SUPPORT;
> > +
> > + return err;
> > +}
> > +EXPORT_SYMBOL_GPL(mmc_uhs2_rescan_try_freq);
> > diff --git a/drivers/mmc/core/uhs2.h b/drivers/mmc/core/uhs2.h
> > new file mode 100644
> > index 000000000000..e3389d4dda3b
> > --- /dev/null
> > +++ b/drivers/mmc/core/uhs2.h
> > @@ -0,0 +1,20 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +/*
> > + * driver/mmc/core/uhs2.h - UHS-II driver
> > + *
> > + * Header file for UHS-II packets, Host Controller registers and I/O
> > + * accessors.
> > + *
> > + * Copyright (C) 2014 Intel Corp, All Rights Reserved.
> > + */
> > +#ifndef MMC_UHS2_H
> > +#define MMC_UHS2_H
> > +
> > +#include <linux/mmc/core.h>
> > +#include <linux/mmc/host.h>
> > +
> > +#define UHS2_PHY_INIT_ERR 1
> > +
> > +int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq);
> > +
> > +#endif /* MMC_UHS2_H */
> > --
> > 2.27.0
> >
>
> Kind regards
> Uffe
Best regards,
Ben
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