On Wed, 23 Oct 2024, Paul Menzel wrote:
> [Cc: +Bjorn, +linux-pci]
>
> Dear Chandra,
>
>
> Thank you for the patch.
>
> First something minor: Should there be a space in your name?
>
> ChandraShekar → Chandra Shekar
>
> `git config --global user.name "…"` can configure this for your git setup.
>
> Also for the summary/title, it’d be great if you used a statement by using a
> verb (in imperative mood):
>
> Add device suspend-resume support
>
> or shorter
>
> Support suspend-resume
>
> Am 23.10.24 um 13:46 schrieb ChandraShekar:
> > This patch contains the changes in driver to support the suspend and
> > resume i.e move the controller to D3 state when the platform is entering
> > into suspend and move the controller to D0 on resume.
>
> It’d be great if you elaborated. Please start by the history, since when Intel
> Bluetooth PCIe have been there, and why until now this support was missing.
>
> Then please describe, what is needed, and what documentation you used to
> implement the support.
>
> Also, please document, how you tested this, including the log messages, and
> also the time it takes to resume.
>
> Is it also possible to use Bluetooth as a wakeup source from suspend?
>
> > Signed-off-by: Kiran K <kiran.k@xxxxxxxxx>
> > Signed-off-by: ChandraShekar <chandrashekar.devegowda@xxxxxxxxx>
> > ---
> > drivers/bluetooth/btintel_pcie.c | 52 ++++++++++++++++++++++++++++++++
> > drivers/bluetooth/btintel_pcie.h | 4 +++
> > 2 files changed, 56 insertions(+)
> >
> > diff --git a/drivers/bluetooth/btintel_pcie.c
> > b/drivers/bluetooth/btintel_pcie.c
> > index fd4a8bd056fa..f2c44b9d7328 100644
> > --- a/drivers/bluetooth/btintel_pcie.c
> > +++ b/drivers/bluetooth/btintel_pcie.c
> > @@ -273,6 +273,12 @@ static int btintel_pcie_reset_bt(struct
> > btintel_pcie_data *data)
> > return reg == 0 ? 0 : -ENODEV;
> > }
> > +static void btintel_pcie_set_persistence_mode(struct btintel_pcie_data
> > *data)
> > +{
> > + btintel_pcie_set_reg_bits(data, BTINTEL_PCIE_CSR_HW_BOOT_CONFIG,
> > + BTINTEL_PCIE_CSR_HW_BOOT_CONFIG_KEEP_ON);
> > +}
> > +
> > /* This function enables BT function by setting
> > BTINTEL_PCIE_CSR_FUNC_CTRL_MAC_INIT bit in
> > * BTINTEL_PCIE_CSR_FUNC_CTRL_REG register and wait for MSI-X with
> > * BTINTEL_PCIE_MSIX_HW_INT_CAUSES_GP0.
> > @@ -297,6 +303,8 @@ static int btintel_pcie_enable_bt(struct
> > btintel_pcie_data *data)
> > */
> > data->boot_stage_cache = 0x0;
> > + btintel_pcie_set_persistence_mode(data);
> > +
> > /* Set MAC_INIT bit to start primary bootloader */
> > reg = btintel_pcie_rd_reg32(data, BTINTEL_PCIE_CSR_FUNC_CTRL_REG);
> > reg &= ~(BTINTEL_PCIE_CSR_FUNC_CTRL_FUNC_INIT |
> > @@ -1653,11 +1661,55 @@ static void btintel_pcie_remove(struct pci_dev
> > *pdev)
> > pci_set_drvdata(pdev, NULL);
> > }
> > +static int btintel_pcie_suspend(struct device *dev)
> > +{
> > + struct btintel_pcie_data *data;
> > + int err;
> > + struct pci_dev *pdev = to_pci_dev(dev);
Extra space.
> > +
> > + data = pci_get_drvdata(pdev);
> > + btintel_pcie_wr_sleep_cntrl(data, BTINTEL_PCIE_STATE_D3_HOT);
> > + data->gp0_received = false;
> > + err = wait_event_timeout(data->gp0_wait_q, data->gp0_received,
> > +
> > msecs_to_jiffies(BTINTEL_DEFAULT_INTR_TIMEOUT_MS));
> > + if (!err) {
> > + bt_dev_err(data->hdev, "failed to receive gp0 interrupt for
> > suspend");
>
> Please include the timeout in the message.
>
> > + goto fail;
> > + }
> > + return 0;
> > +fail:
> > + return -EBUSY;
> > +}
> > +
> > +static int btintel_pcie_resume(struct device *dev)
> > +{
> > + struct btintel_pcie_data *data;
> > + struct pci_dev *pdev = to_pci_dev(dev);
Ditto.
> > + int err;
Why's the order inconsistent compared with suspend func local vars?
> > +
> > + data = pci_get_drvdata(pdev);
> > + btintel_pcie_wr_sleep_cntrl(data, BTINTEL_PCIE_STATE_D0);
> > + data->gp0_received = false;
> > + err = wait_event_timeout(data->gp0_wait_q, data->gp0_received,
> > +
> > msecs_to_jiffies(BTINTEL_DEFAULT_INTR_TIMEOUT_MS));
> > + if (!err) {
> > + bt_dev_err(data->hdev, "failed to receive gp0 interrupt for
> > resume");
>
> Ditto.
>
> > + goto fail;
> > + }
> > + return 0;
> > +fail:
> > + return -EBUSY;
Quite much common code here compared with the suspend side. Perhaps a
helper function would be useful?
> > +}
> > +
> > +static SIMPLE_DEV_PM_OPS(btintel_pcie_pm_ops, btintel_pcie_suspend,
> > + btintel_pcie_resume);
> > +
> > static struct pci_driver btintel_pcie_driver = {
> > .name = KBUILD_MODNAME,
> > .id_table = btintel_pcie_table,
> > .probe = btintel_pcie_probe,
> > .remove = btintel_pcie_remove,
> > + .driver.pm = &btintel_pcie_pm_ops,
> > };
> > module_pci_driver(btintel_pcie_driver);
> > diff --git a/drivers/bluetooth/btintel_pcie.h
> > b/drivers/bluetooth/btintel_pcie.h
> > index f9aada0543c4..38d0c8ea2b6f 100644
> > --- a/drivers/bluetooth/btintel_pcie.h
> > +++ b/drivers/bluetooth/btintel_pcie.h
> > @@ -8,6 +8,7 @@
> > /* Control and Status Register(BTINTEL_PCIE_CSR) */
> > #define BTINTEL_PCIE_CSR_BASE (0x000)
> > +#define BTINTEL_PCIE_CSR_HW_BOOT_CONFIG (BTINTEL_PCIE_CSR_BASE
> > + 0x000)
> > #define BTINTEL_PCIE_CSR_FUNC_CTRL_REG (BTINTEL_PCIE_CSR_BASE
> > + 0x024)
> > #define BTINTEL_PCIE_CSR_HW_REV_REG (BTINTEL_PCIE_CSR_BASE +
> > 0x028)
> > #define BTINTEL_PCIE_CSR_RF_ID_REG (BTINTEL_PCIE_CSR_BASE +
> > 0x09C)
> > @@ -48,6 +49,9 @@
> > #define BTINTEL_PCIE_CSR_MSIX_IVAR_BASE
> > (BTINTEL_PCIE_CSR_MSIX_BASE + 0x0880)
> > #define BTINTEL_PCIE_CSR_MSIX_IVAR(cause)
> > (BTINTEL_PCIE_CSR_MSIX_IVAR_BASE + (cause))
> > +/* CSR HW BOOT CONFIG Register */
> > +#define BTINTEL_PCIE_CSR_HW_BOOT_CONFIG_KEEP_ON (BIT(31))
Extra parenthesis.
--
i.
> > +
> > /* Causes for the FH register interrupts */
> > enum msix_fh_int_causes {
> > BTINTEL_PCIE_MSIX_FH_INT_CAUSES_0 = BIT(0), /* cause 0 */
